Spec 204: harden platform core vocabulary (#234)

## Summary
- add the Spec 204 platform vocabulary foundation, including canonical glossary terms, registry ownership descriptors, canonical operation type and alias resolution, and explicit reason ownership and platform reason-family metadata
- harden platform-facing compare, snapshot, evidence, monitoring, review, and reporting surfaces so they prefer governed-subject and canonical operation semantics while preserving intentional Intune-owned terminology
- extend Spec 204 unit, feature, Filament, and architecture coverage and add the full spec artifacts, checklist, and completed task ledger

## Verification
- ran the focused recent-change Sail verification pack for the new glossary and reason-semantics work
- ran the full Spec 204 quickstart verification pack under Sail
- ran `cd apps/platform && ./vendor/bin/sail bin pint --dirty --format agent`
- ran an integrated-browser smoke pass covering tenant dashboard, operations, operation detail, baseline compare, evidence, reviews, review packs, provider connections, inventory items, backup schedules, onboarding, and the system dashboard/operations/failures/run-detail surfaces

## Notes
- provider registration is unchanged and remains in `bootstrap/providers.php`
- no new destructive actions or asset-registration changes are introduced by this branch

Co-authored-by: Ahmed Darrazi <ahmed.darrazi@live.de>
Reviewed-on: #234

.github/agents/copilot-instructions.md

@@ -180,6 +180,10 @@ ## Active Technologies
 - PostgreSQL through existing tenant-owned and workspace-context models (`InventoryItem`, `InventoryLink`, `TenantPermission`, `EvidenceSnapshot`, `TenantReview`); no schema change planned (196-hard-filament-nativity-cleanup)
 - PHP 8.4.15 + Laravel 12, Filament v5, Livewire v4, Pest v4, Tailwind CSS v4, Laravel Sail, existing `BaselineScope`, `InventoryPolicyTypeMeta`, `BaselineSupportCapabilityGuard`, `BaselineCaptureService`, and `BaselineCompareService` (202-governance-subject-taxonomy)
 - PostgreSQL via existing `baseline_profiles.scope_jsonb`, `baseline_tenant_assignments.override_scope_jsonb`, and `operation_runs.context`; no new tables planned (202-governance-subject-taxonomy)
+- PHP 8.4.15 + Laravel 12, Filament v5, Livewire v4, Pest v4, Laravel Sail, existing `BaselineCompareService`, `CompareBaselineToTenantJob`, `SubjectResolver`, `CurrentStateHashResolver`, `DriftHasher`, `BaselineCompareSummaryAssessor`, and finding lifecycle services (203-baseline-compare-strategy)
+- PostgreSQL via existing baseline snapshots, baseline snapshot items, `operation_runs`, findings, and baseline scope JSON; no new top-level tables planned (203-baseline-compare-strategy)
+- PHP 8.4.15 + Laravel 12, Filament v5, Livewire v4, Pest v4, Laravel Sail, existing `GovernanceSubjectTaxonomyRegistry`, `BaselineScope`, `CompareStrategyRegistry`, `OperationCatalog`, `OperationRunType`, `ReasonTranslator`, `ReasonResolutionEnvelope`, `ProviderReasonTranslator`, and current Filament monitoring or review surfaces (204-platform-core-vocabulary-hardening)
+- PostgreSQL via existing `operation_runs.type`, `operation_runs.context`, `baseline_profiles.scope_jsonb`, `baseline_snapshot_items`, findings, evidence payloads, and current config-backed registries; no new top-level tables planned (204-platform-core-vocabulary-hardening)
 
 - PHP 8.4.15 (feat/005-bulk-operations)
 
@@ -214,8 +218,8 @@ ## Code Style
 PHP 8.4.15: Follow standard conventions
 
 ## Recent Changes
+- 204-platform-core-vocabulary-hardening: Added PHP 8.4.15 + Laravel 12, Filament v5, Livewire v4, Pest v4, Laravel Sail, existing `GovernanceSubjectTaxonomyRegistry`, `BaselineScope`, `CompareStrategyRegistry`, `OperationCatalog`, `OperationRunType`, `ReasonTranslator`, `ReasonResolutionEnvelope`, `ProviderReasonTranslator`, and current Filament monitoring or review surfaces
+- 203-baseline-compare-strategy: Added PHP 8.4.15 + Laravel 12, Filament v5, Livewire v4, Pest v4, Laravel Sail, existing `BaselineCompareService`, `CompareBaselineToTenantJob`, `SubjectResolver`, `CurrentStateHashResolver`, `DriftHasher`, `BaselineCompareSummaryAssessor`, and finding lifecycle services
 - 202-governance-subject-taxonomy: Added PHP 8.4.15 + Laravel 12, Filament v5, Livewire v4, Pest v4, Tailwind CSS v4, Laravel Sail, existing `BaselineScope`, `InventoryPolicyTypeMeta`, `BaselineSupportCapabilityGuard`, `BaselineCaptureService`, and `BaselineCompareService`
-- 196-hard-filament-nativity-cleanup: Added PHP 8.4.15 + Laravel 12, Filament v5, Livewire v4, Pest v4, Tailwind CSS v4, existing `DependencyQueryService`, `DependencyTargetResolver`, `TenantRequiredPermissionsViewModelBuilder`, `ArtifactTruthPresenter`, `WorkspaceContext`, Filament `InteractsWithTable`, Filament `TableComponent`, and existing badge and action-surface helpers
-- 195-action-surface-closure: Added PHP 8.4.15 + Laravel 12, Filament v5, Livewire v4, Pest v4, Tailwind CSS v4, existing `ActionSurfaceDiscovery`, `ActionSurfaceValidator`, `ActionSurfaceExemptions`, `GovernanceActionCatalog`, `UiEnforcement`, `WorkspaceContext`, and existing system/onboarding/auth helpers
 <!-- MANUAL ADDITIONS START -->
 <!-- MANUAL ADDITIONS END -->

.github/skills/giteaflow/SKILL.md

@@ -0,0 +1,8 @@
+---
+name: giteaflow
+description: Describe what this skill does and when to use it. Include keywords that help agents identify relevant tasks.
+---
+
+<!-- Tip: Use /create-skill in chat to generate content with agent assistance -->
+
+comit all changes, push to remote, and create a pull request against dev with gitea mcp

apps/platform/app/Filament/Pages/BaselineCompareLanding.php

@@ -21,6 +21,7 @@
 use App\Support\OperationRunLinks;
 use App\Support\OpsUx\OperationUxPresenter;
 use App\Support\OpsUx\OpsUxBrowserEvents;
+use App\Support\ReasonTranslation\ReasonPresenter;
 use App\Support\Rbac\UiEnforcement;
 use App\Support\Ui\ActionSurface\ActionSurfaceDeclaration;
 use App\Support\Ui\ActionSurface\Enums\ActionSurfaceProfile;
@@ -203,6 +204,10 @@ public function refreshStats(): void
     protected function getViewData(): array
     {
         $evidenceGapSummary = is_array($this->evidenceGapSummary) ? $this->evidenceGapSummary : [];
+        $reasonPresenter = app(ReasonPresenter::class);
+        $reasonSemantics = $reasonPresenter->semantics(
+            $reasonPresenter->forArtifactTruth($this->reasonCode, 'baseline_compare_landing'),
+        );
         $hasCoverageWarnings = in_array($this->coverageStatus, ['warning', 'unproven'], true);
         $evidenceGapsCountValue = is_numeric($evidenceGapSummary['count'] ?? null)
             ? (int) $evidenceGapSummary['count']
@@ -276,6 +281,7 @@ protected function getViewData(): array
             'whyNoFindingsFallback' => $whyNoFindingsFallback,
             'whyNoFindingsColor' => $whyNoFindingsColor,
             'summaryAssessment' => is_array($this->summaryAssessment) ? $this->summaryAssessment : null,
+            'reasonSemantics' => $reasonSemantics,
         ];
     }
 
@@ -381,17 +387,23 @@ private function compareNowAction(): Action
 
                 if (! ($result['ok'] ?? false)) {
                     $reasonCode = is_string($result['reason_code'] ?? null) ? (string) $result['reason_code'] : 'unknown';
+                    $translation = is_array($result['reason_translation'] ?? null) ? $result['reason_translation'] : [];
 
-                    $message = match ($reasonCode) {
-                        \App\Support\Baselines\BaselineReasonCodes::COMPARE_ROLLOUT_DISABLED => 'Full-content baseline compare is currently disabled for controlled rollout.',
-                        \App\Support\Baselines\BaselineReasonCodes::COMPARE_PROFILE_NOT_ACTIVE => 'The assigned baseline profile is not active.',
-                        \App\Support\Baselines\BaselineReasonCodes::COMPARE_NO_ACTIVE_SNAPSHOT,
-                        \App\Support\Baselines\BaselineReasonCodes::COMPARE_NO_CONSUMABLE_SNAPSHOT => 'No complete baseline snapshot is currently available for compare.',
-                        \App\Support\Baselines\BaselineReasonCodes::COMPARE_SNAPSHOT_BUILDING => 'The latest baseline capture is still building. Compare will be available after it completes.',
-                        \App\Support\Baselines\BaselineReasonCodes::COMPARE_SNAPSHOT_INCOMPLETE => 'The latest baseline capture is incomplete. Capture a new baseline before comparing.',
-                        \App\Support\Baselines\BaselineReasonCodes::COMPARE_SNAPSHOT_SUPERSEDED => 'A newer complete baseline snapshot is current. Compare uses the latest complete baseline only.',
-                        default => 'Reason: '.$reasonCode,
-                    };
+                    $message = is_string($translation['short_explanation'] ?? null) && trim((string) $translation['short_explanation']) !== ''
+                        ? trim((string) $translation['short_explanation'])
+                        : match ($reasonCode) {
+                            \App\Support\Baselines\BaselineReasonCodes::COMPARE_ROLLOUT_DISABLED => 'Full-content baseline compare is currently disabled for controlled rollout.',
+                            \App\Support\Baselines\BaselineReasonCodes::COMPARE_PROFILE_NOT_ACTIVE => 'The assigned baseline profile is not active.',
+                            \App\Support\Baselines\BaselineReasonCodes::COMPARE_NO_ACTIVE_SNAPSHOT,
+                            \App\Support\Baselines\BaselineReasonCodes::COMPARE_NO_CONSUMABLE_SNAPSHOT => 'No complete baseline snapshot is currently available for compare.',
+                            \App\Support\Baselines\BaselineReasonCodes::COMPARE_SNAPSHOT_BUILDING => 'The latest baseline capture is still building. Compare will be available after it completes.',
+                            \App\Support\Baselines\BaselineReasonCodes::COMPARE_SNAPSHOT_INCOMPLETE => 'The latest baseline capture is incomplete. Capture a new baseline before comparing.',
+                            \App\Support\Baselines\BaselineReasonCodes::COMPARE_SNAPSHOT_SUPERSEDED => 'A newer complete baseline snapshot is current. Compare uses the latest complete baseline only.',
+                            \App\Support\Baselines\BaselineReasonCodes::COMPARE_INVALID_SCOPE => 'The assigned baseline scope is invalid and must be reviewed before compare can start.',
+                            \App\Support\Baselines\BaselineReasonCodes::COMPARE_UNSUPPORTED_SCOPE => 'The selected governed subjects are not supported by any compare strategy.',
+                            \App\Support\Baselines\BaselineReasonCodes::COMPARE_MIXED_SCOPE => 'The selected governed subjects span multiple compare strategy families and must be narrowed before compare can start.',
+                            default => 'Reason: '.$reasonCode,
+                        };
 
                     Notification::make()
                         ->title('Cannot start comparison')

apps/platform/app/Filament/Pages/BaselineCompareMatrix.php

@@ -14,6 +14,8 @@
 use App\Services\Baselines\BaselineCompareService;
 use App\Support\Auth\Capabilities;
 use App\Support\Baselines\BaselineCompareMatrixBuilder;
+use App\Support\Baselines\BaselineReasonCodes;
+use App\Support\Baselines\Compare\CompareStrategyRegistry;
 use App\Support\Navigation\CanonicalNavigationContext;
 use App\Support\OperationRunLinks;
 use App\Support\OpsUx\OperationUxPresenter;
@@ -128,15 +130,15 @@ public function form(Schema $schema): Schema
                         ])
                             ->schema([
                                 Select::make('draftSelectedPolicyTypes')
-                                    ->label('Policy types')
+                                    ->label('Governed subjects')
                                     ->options(fn (): array => $this->matrixOptions('policyTypeOptions'))
                                     ->multiple()
                                     ->searchable()
                                     ->preload()
                                     ->native(false)
-                                    ->placeholder('All policy types')
+                                    ->placeholder('All governed subjects')
                                     ->helperText(fn (): ?string => $this->matrixOptions('policyTypeOptions') === []
-                                        ? 'Policy type filters appear after a usable reference snapshot is available.'
+                                        ? 'Governed subject filters appear after a usable reference snapshot is available.'
                                         : null)
                                     ->extraFieldWrapperAttributes([
                                         'data-testid' => 'matrix-policy-type-filter',
@@ -246,7 +248,22 @@ protected function getHeaderActions(): array
             ->requireCapability(Capabilities::WORKSPACE_BASELINES_MANAGE)
             ->preserveDisabled()
             ->tooltip('You need workspace baseline manage access to compare the visible assigned set.')
-            ->apply();
+            ->apply()
+            ->tooltip(function (): ?string {
+                $user = auth()->user();
+                $workspace = $this->workspace();
+
+                if ($user instanceof User && $workspace instanceof Workspace) {
+                    /** @var WorkspaceCapabilityResolver $resolver */
+                    $resolver = app(WorkspaceCapabilityResolver::class);
+
+                    if ($resolver->isMember($user, $workspace) && ! $resolver->can($user, $workspace, Capabilities::WORKSPACE_BASELINES_MANAGE)) {
+                        return 'You need workspace baseline manage access to compare the visible assigned set.';
+                    }
+                }
+
+                return $this->compareAssignedTenantsDisabledReason();
+            });
 
         return [
             Action::make('backToBaselineProfile')
@@ -409,7 +426,7 @@ public function activeFilterSummary(): array
         $summary = [];
 
         if ($this->selectedPolicyTypes !== []) {
-            $summary['Policy types'] = count($this->selectedPolicyTypes);
+            $summary['Governed subjects'] = count($this->selectedPolicyTypes);
         }
 
         if ($this->selectedStates !== []) {
@@ -435,7 +452,7 @@ public function stagedFilterSummary(): array
         $summary = [];
 
         if ($this->draftSelectedPolicyTypes !== $this->selectedPolicyTypes) {
-            $summary['Policy types'] = count($this->draftSelectedPolicyTypes);
+            $summary['Governed subjects'] = count($this->draftSelectedPolicyTypes);
         }
 
         if ($this->draftSelectedStates !== $this->selectedStates) {
@@ -616,9 +633,41 @@ private function compareAssignedTenantsDisabledReason(): ?string
             return 'No visible assigned tenants are available for compare.';
         }
 
+        return $this->compareStartReasonMessage($this->compareAssignedTenantsReasonCode());
+    }
+
+    private function compareAssignedTenantsReasonCode(): ?string
+    {
+        try {
+            $scope = $this->getRecord()->normalizedScope();
+        } catch (\Throwable) {
+            return BaselineReasonCodes::COMPARE_INVALID_SCOPE;
+        }
+
+        $selection = app(CompareStrategyRegistry::class)->select($scope);
+
+        if ($selection->isMixed()) {
+            return BaselineReasonCodes::COMPARE_MIXED_SCOPE;
+        }
+
+        if (! $selection->isSupported()) {
+            return BaselineReasonCodes::COMPARE_UNSUPPORTED_SCOPE;
+        }
+
         return null;
     }
 
+    private function compareStartReasonMessage(?string $reasonCode): ?string
+    {
+        return match ($reasonCode) {
+            BaselineReasonCodes::COMPARE_INVALID_SCOPE => 'The assigned baseline scope is invalid and must be reviewed before comparing assigned tenants.',
+            BaselineReasonCodes::COMPARE_UNSUPPORTED_SCOPE => 'The selected governed subjects are not supported by any compare strategy yet.',
+            BaselineReasonCodes::COMPARE_MIXED_SCOPE => 'The selected governed subjects span multiple compare strategy families and must be narrowed before comparing assigned tenants.',
+            'tenant_sync_required' => 'You need tenant sync access for each visible tenant before compare can start.',
+            default => null,
+        };
+    }
+
     private function compareAssignedTenants(): void
     {
         $user = auth()->user();
@@ -639,6 +688,15 @@ private function compareAssignedTenants(): void
             (int) $result['visibleAssignedTenantCount'],
             (int) $result['visibleAssignedTenantCount'] === 1 ? '' : 's',
         );
+        $blockedReasonCodes = collect($result['targets'])
+            ->where('launchState', 'blocked')
+            ->pluck('reasonCode')
+            ->filter(static fn (mixed $reasonCode): bool => is_string($reasonCode) && trim($reasonCode) !== '')
+            ->unique()
+            ->values();
+        $blockedReasonMessage = $blockedReasonCodes->count() === 1
+            ? $this->compareStartReasonMessage((string) $blockedReasonCodes->first())
+            : null;
 
         if ((int) $result['queuedCount'] > 0 || (int) $result['alreadyQueuedCount'] > 0) {
             OpsUxBrowserEvents::dispatchRunEnqueued($this);
@@ -661,7 +719,7 @@ private function compareAssignedTenants(): void
         } else {
             Notification::make()
                 ->title('No baseline compares were started')
-                ->body($summary)
+                ->body($blockedReasonMessage !== null ? $blockedReasonMessage.' '.$summary : $summary)
                 ->warning()
                 ->send();
         }

apps/platform/app/Filament/Resources/BaselineProfileResource.php

@@ -25,6 +25,7 @@
 use App\Support\Baselines\BaselineFullContentRolloutGate;
 use App\Support\Baselines\BaselineProfileStatus;
 use App\Support\Baselines\BaselineReasonCodes;
+use App\Support\Baselines\Compare\CompareStrategyRegistry;
 use App\Support\Filament\FilterOptionCatalog;
 use App\Support\Inventory\InventoryPolicyTypeMeta;
 use App\Support\Navigation\CrossResourceNavigationMatrix;
@@ -807,6 +808,7 @@ private static function compareReadinessLabel(BaselineProfile $profile): string
     {
         return match (self::compareAvailabilityReason($profile)) {
             BaselineReasonCodes::COMPARE_INVALID_SCOPE => 'Invalid scope',
+            BaselineReasonCodes::COMPARE_MIXED_SCOPE => 'Mixed strategy scope',
             BaselineReasonCodes::COMPARE_UNSUPPORTED_SCOPE => 'Unsupported governed subjects',
             default => self::compareAvailabilityEnvelope($profile)?->operatorLabel ?? 'Ready',
         };
@@ -818,6 +820,7 @@ private static function compareReadinessColor(BaselineProfile $profile): string
             null => 'success',
             BaselineReasonCodes::COMPARE_PROFILE_NOT_ACTIVE => 'gray',
             BaselineReasonCodes::COMPARE_INVALID_SCOPE,
+            BaselineReasonCodes::COMPARE_MIXED_SCOPE,
             BaselineReasonCodes::COMPARE_UNSUPPORTED_SCOPE => 'danger',
             default => 'warning',
         };
@@ -829,6 +832,7 @@ private static function compareReadinessIcon(BaselineProfile $profile): ?string
             null => 'heroicon-m-check-badge',
             BaselineReasonCodes::COMPARE_PROFILE_NOT_ACTIVE => 'heroicon-m-pause-circle',
             BaselineReasonCodes::COMPARE_INVALID_SCOPE,
+            BaselineReasonCodes::COMPARE_MIXED_SCOPE,
             BaselineReasonCodes::COMPARE_UNSUPPORTED_SCOPE => 'heroicon-m-no-symbol',
             default => 'heroicon-m-exclamation-triangle',
         };
@@ -838,6 +842,7 @@ private static function profileNextStep(BaselineProfile $profile): string
     {
         return match (self::compareAvailabilityReason($profile)) {
             BaselineReasonCodes::COMPARE_INVALID_SCOPE,
+            BaselineReasonCodes::COMPARE_MIXED_SCOPE,
             BaselineReasonCodes::COMPARE_UNSUPPORTED_SCOPE => 'Review the governed subject selection before starting compare.',
             default => self::compareAvailabilityEnvelope($profile)?->guidanceText() ?? 'No action needed.',
         };
@@ -873,7 +878,13 @@ private static function compareAvailabilityReason(BaselineProfile $profile): ?st
             return BaselineReasonCodes::COMPARE_INVALID_SCOPE;
         }
 
-        if (! $scope->operationEligibility('compare')['ok']) {
+        $selection = app(CompareStrategyRegistry::class)->select($scope);
+
+        if ($selection->isMixed()) {
+            return BaselineReasonCodes::COMPARE_MIXED_SCOPE;
+        }
+
+        if (! $selection->isSupported()) {
             return BaselineReasonCodes::COMPARE_UNSUPPORTED_SCOPE;
         }
 

apps/platform/app/Filament/Resources/BaselineProfileResource/Pages/ViewBaselineProfile.php

@@ -250,19 +250,23 @@ private function compareNowAction(): Action
 
                 if (! ($result['ok'] ?? false)) {
                     $reasonCode = is_string($result['reason_code'] ?? null) ? (string) $result['reason_code'] : 'unknown';
+                    $translation = is_array($result['reason_translation'] ?? null) ? $result['reason_translation'] : [];
 
-                    $message = match ($reasonCode) {
-                        BaselineReasonCodes::COMPARE_ROLLOUT_DISABLED => 'Full-content baseline compare is currently disabled for controlled rollout.',
-                        BaselineReasonCodes::COMPARE_PROFILE_NOT_ACTIVE => 'This baseline profile is not active.',
-                        BaselineReasonCodes::COMPARE_NO_ACTIVE_SNAPSHOT,
-                        BaselineReasonCodes::COMPARE_NO_CONSUMABLE_SNAPSHOT => 'This baseline profile has no complete snapshot available for compare yet.',
-                        BaselineReasonCodes::COMPARE_SNAPSHOT_BUILDING => 'The latest baseline capture is still building. Compare will be available after it completes.',
-                        BaselineReasonCodes::COMPARE_SNAPSHOT_INCOMPLETE => 'The latest baseline capture is incomplete. Capture a new baseline before comparing.',
-                        BaselineReasonCodes::COMPARE_SNAPSHOT_SUPERSEDED => 'A newer complete snapshot is current. Compare uses the latest complete baseline only.',
-                        BaselineReasonCodes::COMPARE_INVALID_SCOPE => 'This baseline profile has an invalid governed-subject scope. Review the baseline definition before comparing.',
-                        BaselineReasonCodes::COMPARE_UNSUPPORTED_SCOPE => 'This baseline profile includes governed subjects that are not currently supported for compare.',
-                        default => 'Reason: '.str_replace('.', ' ', $reasonCode),
-                    };
+                    $message = is_string($translation['short_explanation'] ?? null) && trim((string) $translation['short_explanation']) !== ''
+                        ? trim((string) $translation['short_explanation'])
+                        : match ($reasonCode) {
+                            BaselineReasonCodes::COMPARE_ROLLOUT_DISABLED => 'Full-content baseline compare is currently disabled for controlled rollout.',
+                            BaselineReasonCodes::COMPARE_PROFILE_NOT_ACTIVE => 'This baseline profile is not active.',
+                            BaselineReasonCodes::COMPARE_NO_ACTIVE_SNAPSHOT,
+                            BaselineReasonCodes::COMPARE_NO_CONSUMABLE_SNAPSHOT => 'This baseline profile has no complete snapshot available for compare yet.',
+                            BaselineReasonCodes::COMPARE_SNAPSHOT_BUILDING => 'The latest baseline capture is still building. Compare will be available after it completes.',
+                            BaselineReasonCodes::COMPARE_SNAPSHOT_INCOMPLETE => 'The latest baseline capture is incomplete. Capture a new baseline before comparing.',
+                            BaselineReasonCodes::COMPARE_SNAPSHOT_SUPERSEDED => 'A newer complete snapshot is current. Compare uses the latest complete baseline only.',
+                            BaselineReasonCodes::COMPARE_INVALID_SCOPE => 'This baseline profile has an invalid governed-subject scope. Review the baseline definition before comparing.',
+                            BaselineReasonCodes::COMPARE_UNSUPPORTED_SCOPE => 'This baseline profile includes governed subjects that are not currently supported for compare.',
+                            BaselineReasonCodes::COMPARE_MIXED_SCOPE => 'This baseline profile mixes governed subjects that require different compare strategies. Narrow the selection before comparing.',
+                            default => 'Reason: '.str_replace('.', ' ', $reasonCode),
+                        };
 
                     Notification::make()
                         ->title('Cannot start comparison')

apps/platform/app/Filament/Resources/OperationRunResource.php

@@ -31,6 +31,7 @@
 use App\Support\OpsUx\RunDurationInsights;
 use App\Support\OpsUx\SummaryCountsNormalizer;
 use App\Support\ReasonTranslation\ReasonPresenter;
+use App\Support\ReasonTranslation\ReasonResolutionEnvelope;
 use App\Support\RestoreSafety\RestoreSafetyResolver;
 use App\Support\Tenants\ReferencedTenantLifecyclePresentation;
 use App\Support\Ui\ActionSurface\ActionSurfaceDeclaration;
@@ -219,6 +220,15 @@ public static function table(Table $table): Table
                             ->all();
 
                         return FilterOptionCatalog::operationTypes(array_keys($types));
+                    })
+                    ->query(function (Builder $query, array $data): Builder {
+                        $value = data_get($data, 'value');
+
+                        if (! is_string($value) || trim($value) === '') {
+                            return $query;
+                        }
+
+                        return $query->whereIn('type', OperationCatalog::rawValuesForCanonical($value));
                     }),
                 Tables\Filters\SelectFilter::make('status')
                     ->options(BadgeCatalog::options(BadgeDomain::OperationRunStatus, OperationRunStatus::values())),
@@ -268,6 +278,7 @@ private static function enterpriseDetailPage(OperationRun $record): \App\Support
             : null;
         $artifactTruth = static::artifactTruthEnvelope($record);
         $operatorExplanation = $artifactTruth?->operatorExplanation;
+        $reasonEnvelope = app(ReasonPresenter::class)->forOperationRun($record, 'run_detail');
         $primaryNextStep = static::resolvePrimaryNextStep($record, $artifactTruth, $operatorExplanation);
         $restoreContinuation = static::restoreContinuation($record);
         $supportingGroups = static::supportingGroups(
@@ -275,6 +286,7 @@ private static function enterpriseDetailPage(OperationRun $record): \App\Support
             factory: $factory,
             referencedTenantLifecycle: $referencedTenantLifecycle,
             operatorExplanation: $operatorExplanation,
+            reasonEnvelope: $reasonEnvelope,
             primaryNextStep: $primaryNextStep,
         );
 
@@ -439,7 +451,7 @@ private static function enterpriseDetailPage(OperationRun $record): \App\Support
                         id: 'baseline_compare_gap_details',
                         kind: 'type_specific_detail',
                         title: 'Evidence gap details',
-                        description: 'Policies affected by evidence gaps, grouped by reason and searchable by reason, policy type, or subject key.',
+                        description: 'Governed subjects affected by evidence gaps, grouped by reason and searchable by reason, governed subject, or subject key.',
                         view: 'filament.infolists.entries.evidence-gap-subjects',
                         viewData: [
                             'summary' => $gapSummary,
@@ -537,10 +549,12 @@ private static function supportingGroups(
         \App\Support\Ui\EnterpriseDetail\EnterpriseDetailSectionFactory $factory,
         ?ReferencedTenantLifecyclePresentation $referencedTenantLifecycle,
         ?OperatorExplanationPattern $operatorExplanation,
+        ?ReasonResolutionEnvelope $reasonEnvelope,
         array $primaryNextStep,
     ): array {
         $groups = [];
         $hasElevatedLifecycleState = static::lifecycleAttentionSummary($record) !== null;
+        $reasonSemantics = app(ReasonPresenter::class)->semantics($reasonEnvelope);
 
         $guidanceItems = array_values(array_filter([
             $operatorExplanation instanceof OperatorExplanationPattern && $operatorExplanation->coverageStatement !== null
@@ -579,6 +593,24 @@ private static function supportingGroups(
             );
         }
 
+        $reasonSemanticsItems = array_values(array_filter([
+            is_string($reasonSemantics['owner_label'] ?? null)
+                ? $factory->keyFact('Reason owner', (string) $reasonSemantics['owner_label'])
+                : null,
+            is_string($reasonSemantics['family_label'] ?? null)
+                ? $factory->keyFact('Platform reason family', (string) $reasonSemantics['family_label'])
+                : null,
+        ]));
+
+        if ($reasonSemanticsItems !== []) {
+            $groups[] = $factory->supportingFactsCard(
+                kind: 'reason_semantics',
+                title: 'Explanation semantics',
+                items: $reasonSemanticsItems,
+                description: 'Platform meaning stays separate from domain-specific diagnostic detail during rollout.',
+            );
+        }
+
         $lifecycleItems = array_values(array_filter([
             $referencedTenantLifecycle !== null
                 ? $factory->keyFact(
@@ -957,6 +989,49 @@ private static function baselineCompareFacts(
             );
         }
 
+        $strategy = data_get($context, 'baseline_compare.strategy');
+        if (is_array($strategy)) {
+            $strategyKey = is_string($strategy['key'] ?? null) && trim((string) $strategy['key']) !== ''
+                ? trim((string) $strategy['key'])
+                : null;
+            $selectionState = is_string($strategy['selection_state'] ?? null) && trim((string) $strategy['selection_state']) !== ''
+                ? trim((string) $strategy['selection_state'])
+                : null;
+            $operatorReason = is_string($strategy['operator_reason'] ?? null) && trim((string) $strategy['operator_reason']) !== ''
+                ? trim((string) $strategy['operator_reason'])
+                : null;
+            $stateCounts = is_array($strategy['state_counts'] ?? null)
+                ? array_filter(
+                    array_map(static fn (mixed $count): int => (int) $count, $strategy['state_counts']),
+                    static fn (int $count): bool => $count > 0,
+                )
+                : [];
+
+            if ($strategyKey !== null) {
+                $facts[] = $factory->keyFact(
+                    'Compare strategy',
+                    \Illuminate\Support\Str::of($strategyKey)->replace('_', ' ')->headline()->toString(),
+                );
+            }
+
+            if ($selectionState !== null) {
+                $facts[] = $factory->keyFact(
+                    'Strategy selection',
+                    \Illuminate\Support\Str::of($selectionState)->replace('_', ' ')->headline()->toString(),
+                    $operatorReason,
+                );
+            }
+
+            if ($stateCounts !== []) {
+                $facts[] = $factory->keyFact(
+                    'Strategy subject states',
+                    collect($stateCounts)
+                        ->map(static fn (int $count, string $state): string => \Illuminate\Support\Str::of($state)->replace('_', ' ')->headline()->append(' ', (string) $count)->toString())
+                        ->implode(', '),
+                );
+            }
+        }
+
         if ((int) ($gapSummary['count'] ?? 0) > 0) {
             $facts[] = $factory->keyFact(
                 'Evidence gap detail',
@@ -1009,6 +1084,9 @@ private static function baselineCompareEvidencePayload(OperationRun $record): ar
                 ? (int) data_get($context, 'baseline_compare.evidence_gaps.count')
                 : null,
             'resume_token' => data_get($context, 'baseline_compare.resume_token'),
+            'strategy' => is_array(data_get($context, 'baseline_compare.strategy'))
+                ? data_get($context, 'baseline_compare.strategy')
+                : null,
             'evidence_capture' => is_array(data_get($context, 'baseline_compare.evidence_capture'))
                 ? data_get($context, 'baseline_compare.evidence_capture')
                 : null,

apps/platform/app/Filament/Resources/TenantReviewResource.php

@@ -21,6 +21,7 @@
 use App\Support\OperationRunLinks;
 use App\Support\OperationRunType;
 use App\Support\OpsUx\OperationUxPresenter;
+use App\Support\ReasonTranslation\ReasonPresenter;
 use App\Support\Rbac\UiEnforcement;
 use App\Support\TenantReviewCompletenessState;
 use App\Support\TenantReviewStatus;
@@ -564,9 +565,12 @@ private static function reviewCompletenessCountLabel(string $state): string
     private static function summaryPresentation(TenantReview $record): array
     {
         $summary = is_array($record->summary) ? $record->summary : [];
+        $truthEnvelope = static::truthEnvelope($record);
+        $reasonPresenter = app(ReasonPresenter::class);
 
         return [
-            'operator_explanation' => static::truthEnvelope($record)->operatorExplanation?->toArray(),
+            'operator_explanation' => $truthEnvelope->operatorExplanation?->toArray(),
+            'reason_semantics' => $reasonPresenter->semantics($truthEnvelope->reason?->toReasonResolutionEnvelope()),
             'highlights' => is_array($summary['highlights'] ?? null) ? $summary['highlights'] : [],
             'next_actions' => is_array($summary['recommended_next_actions'] ?? null) ? $summary['recommended_next_actions'] : [],
             'publish_blockers' => is_array($summary['publish_blockers'] ?? null) ? $summary['publish_blockers'] : [],

apps/platform/app/Filament/Widgets/Tenant/TenantReviewPackCard.php

@@ -14,6 +14,7 @@
 use App\Support\OperationRunType;
 use App\Support\OpsUx\OperationUxPresenter;
 use App\Support\OpsUx\OpsUxBrowserEvents;
+use App\Support\ReasonTranslation\ReasonPresenter;
 use App\Support\ReviewPackStatus;
 use Filament\Actions\Action;
 use Filament\Facades\Filament;
@@ -131,7 +132,7 @@ protected function getViewData(): array
         $canManage = $isTenantMember && $user->can(Capabilities::REVIEW_PACK_MANAGE, $tenant);
 
         $latestPack = ReviewPack::query()
-            ->with('tenantReview')
+            ->with(['tenantReview', 'operationRun'])
             ->where('tenant_id', (int) $tenant->getKey())
             ->orderByDesc('created_at')
             ->orderByDesc('id')
@@ -166,9 +167,24 @@ protected function getViewData(): array
         }
 
         $failedReason = null;
+        $failedReasonDetail = null;
+        $failedReasonSemantics = null;
+
         if ($statusEnum === ReviewPackStatus::Failed && $latestPack->operationRun) {
+            $reasonPresenter = app(ReasonPresenter::class);
+            $failedEnvelope = $reasonPresenter->forOperationRun($latestPack->operationRun, 'review_pack_widget');
+
+            if ($failedEnvelope !== null) {
+                $failedReason = $failedEnvelope->operatorLabel;
+                $failedReasonDetail = $failedEnvelope->shortExplanation;
+                $failedReasonSemantics = $reasonPresenter->semantics($failedEnvelope);
+            }
+
             $opContext = is_array($latestPack->operationRun->context) ? $latestPack->operationRun->context : [];
-            $failedReason = (string) ($opContext['reason_code'] ?? 'Unknown error');
+
+            if ($failedReason === null) {
+                $failedReason = (string) ($opContext['reason_code'] ?? 'Unknown error');
+            }
         }
 
         return [
@@ -180,6 +196,8 @@ protected function getViewData(): array
             'canManage' => $canManage,
             'downloadUrl' => $downloadUrl,
             'failedReason' => $failedReason,
+            'failedReasonDetail' => $failedReasonDetail,
+            'failedReasonSemantics' => $failedReasonSemantics,
             'reviewUrl' => $reviewUrl,
         ];
     }
@@ -208,6 +226,8 @@ private function emptyState(): array
             'canManage' => false,
             'downloadUrl' => null,
             'failedReason' => null,
+            'failedReasonDetail' => null,
+            'failedReasonSemantics' => null,
             'reviewUrl' => null,
         ];
     }

apps/platform/app/Jobs/CompareBaselineToTenantJob.php

@@ -42,6 +42,13 @@
 use App\Support\Baselines\BaselineReasonCodes;
 use App\Support\Baselines\BaselineScope;
 use App\Support\Baselines\BaselineSubjectKey;
+use App\Support\Baselines\Compare\CompareFindingCandidate;
+use App\Support\Baselines\Compare\CompareOrchestrationContext;
+use App\Support\Baselines\Compare\CompareState;
+use App\Support\Baselines\Compare\CompareStrategyRegistry;
+use App\Support\Baselines\Compare\CompareStrategySelection;
+use App\Support\Baselines\Compare\CompareSubjectResult;
+use App\Support\Baselines\Compare\StrategySelectionState;
 use App\Support\Baselines\PolicyVersionCapturePurpose;
 use App\Support\Baselines\SubjectResolver;
 use App\Support\Inventory\InventoryCoverage;
@@ -102,6 +109,7 @@ public function handle(
         ?BaselineContentCapturePhase $contentCapturePhase = null,
         ?BaselineFullContentRolloutGate $rolloutGate = null,
         ?ContentEvidenceProvider $contentEvidenceProvider = null,
+        ?CompareStrategyRegistry $compareStrategyRegistry = null,
     ): void {
         $settingsResolver ??= app(SettingsResolver::class);
         $baselineAutoCloseService ??= app(BaselineAutoCloseService::class);
@@ -111,6 +119,7 @@ public function handle(
         $contentCapturePhase ??= app(BaselineContentCapturePhase::class);
         $rolloutGate ??= app(BaselineFullContentRolloutGate::class);
         $contentEvidenceProvider ??= app(ContentEvidenceProvider::class);
+        $compareStrategyRegistry ??= app(CompareStrategyRegistry::class);
 
         if (! $this->operationRun instanceof OperationRun) {
             $this->fail(new RuntimeException('OperationRun context is required for CompareBaselineToTenantJob.'));
@@ -339,6 +348,44 @@ public function handle(
         $snapshot = $snapshotResolution['snapshot'];
         $snapshotId = (int) $snapshot->getKey();
 
+        $strategySelection = $compareStrategyRegistry->select($effectiveScope);
+        $context = $this->withCompareStrategySelection($context, $strategySelection);
+        $this->operationRun->update(['context' => $context]);
+        $this->operationRun->refresh();
+
+        if (! $strategySelection->isSupported()) {
+            $this->auditStarted(
+                auditLogger: $auditLogger,
+                tenant: $tenant,
+                profile: $profile,
+                initiator: $initiator,
+                captureMode: $captureMode,
+                subjectsTotal: 0,
+                effectiveScope: $effectiveScope,
+            );
+
+            $this->completeWithCoverageWarning(
+                operationRunService: $operationRunService,
+                auditLogger: $auditLogger,
+                tenant: $tenant,
+                profile: $profile,
+                initiator: $initiator,
+                inventorySyncRun: $inventorySyncRun,
+                coverageProof: true,
+                effectiveTypes: $effectiveTypes,
+                coveredTypes: $coveredTypes,
+                uncoveredTypes: $uncoveredTypes,
+                errorsRecorded: max(1, count($coveredTypes !== [] ? $coveredTypes : $effectiveTypes)),
+                captureMode: $captureMode,
+                reasonCode: BaselineCompareReasonCode::UnsupportedSubjects,
+                evidenceGapsByReason: [
+                    $this->strategySelectionGapReason($strategySelection) => max(1, count($coveredTypes !== [] ? $coveredTypes : $effectiveTypes)),
+                ],
+            );
+
+            return;
+        }
+
         $since = $snapshot->captured_at instanceof \DateTimeInterface
             ? CarbonImmutable::instance($snapshot->captured_at)
             : null;
@@ -459,32 +506,79 @@ public function handle(
             resolvedMetaEvidence: $resolvedCurrentMetaEvidence,
         );
 
-        $baselinePolicyVersionResolver = app(BaselinePolicyVersionResolver::class);
-        $driftHasher = app(DriftHasher::class);
-        $settingsNormalizer = app(SettingsNormalizer::class);
-        $assignmentsNormalizer = app(AssignmentsNormalizer::class);
-        $scopeTagsNormalizer = app(ScopeTagsNormalizer::class);
-
-        $computeResult = $this->computeDrift(
-            tenant: $tenant,
+        $strategy = $compareStrategyRegistry->resolve($strategySelection->strategyKey);
+        $orchestrationContext = new CompareOrchestrationContext(
+            workspaceId: (int) $workspace->getKey(),
+            tenantId: (int) $tenant->getKey(),
             baselineProfileId: (int) $profile->getKey(),
             baselineSnapshotId: (int) $snapshot->getKey(),
-            compareOperationRunId: (int) $this->operationRun->getKey(),
-            inventorySyncRunId: (int) $inventorySyncRun->getKey(),
-            baselineItems: $baselineItems,
-            currentItems: $currentItems,
-            resolvedCurrentEvidence: $resolvedEffectiveCurrentEvidence,
-            severityMapping: $this->resolveSeverityMapping($workspace, $settingsResolver),
-            baselinePolicyVersionResolver: $baselinePolicyVersionResolver,
-            hasher: $driftHasher,
-            settingsNormalizer: $settingsNormalizer,
-            assignmentsNormalizer: $assignmentsNormalizer,
-            scopeTagsNormalizer: $scopeTagsNormalizer,
-            contentEvidenceProvider: $contentEvidenceProvider,
+            operationRunId: (int) $this->operationRun->getKey(),
+            normalizedScope: $effectiveScope->toStoredJsonb(),
+            strategySelection: $strategySelection,
+            coverageContext: [
+                'inventory_sync_run_id' => (int) $inventorySyncRun->getKey(),
+                'effective_types' => $effectiveTypes,
+                'covered_types' => $coveredTypes,
+                'uncovered_types' => $uncoveredTypes,
+            ],
+            launchContext: is_array($context['baseline_compare'] ?? null) ? $context['baseline_compare'] : [],
         );
-        $driftResults = $computeResult['drift'];
-        $driftGaps = $computeResult['evidence_gaps'];
-        $rbacRoleDefinitionSummary = $computeResult['rbac_role_definitions'];
+
+        try {
+            $compareResult = $strategy->compare(
+                context: $orchestrationContext,
+                tenant: $tenant,
+                baselineItems: $baselineItems,
+                currentItems: $currentItems,
+                resolvedCurrentEvidence: $resolvedEffectiveCurrentEvidence,
+                severityMapping: $this->resolveSeverityMapping($workspace, $settingsResolver),
+            );
+        } catch (\Throwable $exception) {
+            $failedContext = $this->withCompareStrategyDiagnostics(
+                context: is_array($this->operationRun->context) ? $this->operationRun->context : [],
+                strategySelection: $strategySelection,
+                executionDiagnostics: [
+                    'failed' => true,
+                    'exception_class' => $exception::class,
+                ],
+            );
+
+            $this->operationRun->update(['context' => $failedContext]);
+            $this->operationRun->refresh();
+
+            $this->completeWithCoverageWarning(
+                operationRunService: $operationRunService,
+                auditLogger: $auditLogger,
+                tenant: $tenant,
+                profile: $profile,
+                initiator: $initiator,
+                inventorySyncRun: $inventorySyncRun,
+                coverageProof: true,
+                effectiveTypes: $effectiveTypes,
+                coveredTypes: $coveredTypes,
+                uncoveredTypes: $uncoveredTypes,
+                errorsRecorded: max(1, count($coveredTypes !== [] ? $coveredTypes : $effectiveTypes)),
+                captureMode: $captureMode,
+                reasonCode: BaselineCompareReasonCode::StrategyFailed,
+                evidenceGapsByReason: [
+                    'strategy_failed' => max(1, count($coveredTypes !== [] ? $coveredTypes : $effectiveTypes)),
+                ],
+            );
+
+            return;
+        }
+
+        $normalizedStrategyResults = $this->normalizeStrategySubjectResults($compareResult['subject_results'] ?? []);
+        $driftResults = $normalizedStrategyResults['drift_results'];
+        $driftGaps = $normalizedStrategyResults['gap_counts'];
+        $rbacRoleDefinitionSummary = is_array($compareResult['diagnostics']['rbac_role_definitions'] ?? null)
+            ? $compareResult['diagnostics']['rbac_role_definitions']
+            : $this->emptyRbacRoleDefinitionSummary();
+        $strategyGapSubjects = $normalizedStrategyResults['gap_subjects'];
+        $strategyStateCounts = $normalizedStrategyResults['state_counts'];
+        $strategyDiagnostics = is_array($compareResult['diagnostics'] ?? null)
+            ? $compareResult['diagnostics']
+            : [];
 
         $upsertResult = $this->upsertFindings(
             $tenant,
@@ -502,7 +596,7 @@ public function handle(
         $gapSubjects = $this->collectGapSubjects(
             ambiguousKeys: $ambiguousKeys,
             phaseGapSubjects: $phaseGapSubjects ?? [],
-            driftGapSubjects: $computeResult['evidence_gap_subjects'] ?? [],
+            driftGapSubjects: $strategyGapSubjects,
         );
 
         $summaryCounts = [
@@ -565,6 +659,9 @@ public function handle(
         } elseif (count($driftResults) === 0) {
             $reasonCode = match (true) {
                 $uncoveredTypes !== [] => BaselineCompareReasonCode::CoverageUnproven,
+                ($strategyStateCounts[CompareState::Failed->value] ?? 0) > 0 => BaselineCompareReasonCode::StrategyFailed,
+                ($strategyStateCounts[CompareState::Ambiguous->value] ?? 0) > 0 => BaselineCompareReasonCode::AmbiguousSubjects,
+                ($strategyStateCounts[CompareState::Unsupported->value] ?? 0) > 0 => BaselineCompareReasonCode::UnsupportedSubjects,
                 $resumeToken !== null || $gapsCount > 0 => BaselineCompareReasonCode::EvidenceCaptureIncomplete,
                 default => BaselineCompareReasonCode::NoDriftDetected,
             };
@@ -577,6 +674,11 @@ public function handle(
                 'inventory_sync_run_id' => (int) $inventorySyncRun->getKey(),
                 'since' => $since?->toIso8601String(),
                 'subjects_total' => $subjectsTotal,
+                'strategy' => $this->strategyContext(
+                    strategySelection: $strategySelection,
+                    executionDiagnostics: $strategyDiagnostics,
+                    stateCounts: $strategyStateCounts,
+                ),
                 'evidence_capture' => $phaseStats,
                 'evidence_gaps' => [
                     'count' => $gapsCount,
@@ -994,6 +1096,193 @@ private function withCompareReasonTranslation(array $context, ?string $reasonCod
         return $context;
     }
 
+    /**
+     * @param  array<string, mixed>  $context
+     * @return array<string, mixed>
+     */
+    private function withCompareStrategySelection(array $context, CompareStrategySelection $strategySelection): array
+    {
+        $context['baseline_compare'] = array_merge(
+            is_array($context['baseline_compare'] ?? null) ? $context['baseline_compare'] : [],
+            [
+                'strategy' => $this->strategyContext($strategySelection),
+            ],
+        );
+
+        return $context;
+    }
+
+    /**
+     * @param  array<string, mixed>  $context
+     * @param  array<string, mixed>  $executionDiagnostics
+     * @return array<string, mixed>
+     */
+    private function withCompareStrategyDiagnostics(
+        array $context,
+        CompareStrategySelection $strategySelection,
+        array $executionDiagnostics,
+        array $stateCounts = [],
+    ): array {
+        $context['baseline_compare'] = array_merge(
+            is_array($context['baseline_compare'] ?? null) ? $context['baseline_compare'] : [],
+            [
+                'strategy' => $this->strategyContext($strategySelection, $executionDiagnostics, $stateCounts),
+            ],
+        );
+
+        return $context;
+    }
+
+    /**
+     * @param  array<string, mixed>  $executionDiagnostics
+     * @param  array<string, int>  $stateCounts
+     * @return array{
+     *   key: ?string,
+     *   selection_state: string,
+     *   matched_scope_entries: list<array<string, mixed>>,
+     *   rejected_scope_entries: list<array<string, mixed>>,
+     *   operator_reason: string,
+     *   diagnostics: array<string, mixed>,
+     *   execution_diagnostics: array<string, mixed>,
+     *   state_counts: array<string, int>
+     * }
+     */
+    private function strategyContext(
+        CompareStrategySelection $strategySelection,
+        array $executionDiagnostics = [],
+        array $stateCounts = [],
+    ): array {
+        return [
+            'key' => $strategySelection->strategyKey?->value,
+            'selection_state' => $strategySelection->selectionState->value,
+            'matched_scope_entries' => $strategySelection->matchedScopeEntries,
+            'rejected_scope_entries' => $strategySelection->rejectedScopeEntries,
+            'operator_reason' => $strategySelection->operatorReason,
+            'diagnostics' => $strategySelection->diagnostics,
+            'execution_diagnostics' => $executionDiagnostics,
+            'state_counts' => $stateCounts,
+        ];
+    }
+
+    private function strategySelectionGapReason(CompareStrategySelection $strategySelection): string
+    {
+        return $strategySelection->selectionState === StrategySelectionState::Mixed
+            ? 'mixed_scope'
+            : 'unsupported_subjects';
+    }
+
+    /**
+     * @param  mixed  $subjectResults
+     * @return array{
+     *   drift_results: array<int, array{change_type: string, severity: string, evidence_fidelity: string, subject_type: string, subject_external_id: string, subject_key: string, policy_type: string, baseline_hash: string, current_hash: string, evidence: array<string, mixed>}>,
+     *   gap_counts: array<string, int>,
+     *   gap_subjects: list<array<string, mixed>>,
+     *   state_counts: array<string, int>
+     * }
+     */
+    private function normalizeStrategySubjectResults(mixed $subjectResults): array
+    {
+        if (! is_array($subjectResults)) {
+            return [
+                'drift_results' => [],
+                'gap_counts' => [],
+                'gap_subjects' => [],
+                'state_counts' => [],
+            ];
+        }
+
+        $driftResults = [];
+        $gapCounts = [];
+        $gapSubjects = [];
+        $stateCounts = [];
+
+        foreach ($subjectResults as $subjectResult) {
+            if (! $subjectResult instanceof CompareSubjectResult) {
+                continue;
+            }
+
+            $state = $subjectResult->compareState->value;
+            $stateCounts[$state] = ($stateCounts[$state] ?? 0) + 1;
+
+            if ($subjectResult->compareState === CompareState::Drift && $subjectResult->findingCandidate instanceof CompareFindingCandidate) {
+                $driftResults[] = [
+                    'change_type' => $subjectResult->findingCandidate->changeType,
+                    'severity' => $subjectResult->findingCandidate->severity,
+                    'subject_type' => $subjectResult->projection->platformSubjectClass,
+                    'subject_external_id' => $subjectResult->subjectIdentity->externalSubjectId ?? '',
+                    'subject_key' => $subjectResult->subjectIdentity->subjectKey,
+                    'policy_type' => $subjectResult->subjectIdentity->subjectTypeKey,
+                    'evidence_fidelity' => $subjectResult->evidenceQuality,
+                    'baseline_hash' => is_string(data_get($subjectResult->findingCandidate->evidencePayload, 'baseline.hash'))
+                        ? (string) data_get($subjectResult->findingCandidate->evidencePayload, 'baseline.hash')
+                        : '',
+                    'current_hash' => is_string(data_get($subjectResult->findingCandidate->evidencePayload, 'current.hash'))
+                        ? (string) data_get($subjectResult->findingCandidate->evidencePayload, 'current.hash')
+                        : '',
+                    'evidence' => $subjectResult->findingCandidate->evidencePayload,
+                ];
+
+                continue;
+            }
+
+            if (! $subjectResult->isGapState()) {
+                continue;
+            }
+
+            $reasonCode = $subjectResult->gapReasonCode() ?? $this->defaultGapReasonForState($subjectResult->compareState);
+            $gapCounts[$reasonCode] = ($gapCounts[$reasonCode] ?? 0) + 1;
+            $gapSubjects[] = $subjectResult->gapRecord() ?? $this->fallbackGapRecord($subjectResult, $reasonCode);
+        }
+
+        ksort($gapCounts);
+        ksort($stateCounts);
+
+        return [
+            'drift_results' => $driftResults,
+            'gap_counts' => $gapCounts,
+            'gap_subjects' => $gapSubjects,
+            'state_counts' => $stateCounts,
+        ];
+    }
+
+    private function defaultGapReasonForState(CompareState $state): string
+    {
+        return match ($state) {
+            CompareState::Unsupported => 'unsupported_subject',
+            CompareState::Ambiguous => 'ambiguous_match',
+            CompareState::Failed => 'strategy_failed',
+            default => 'missing_current',
+        };
+    }
+
+    /**
+     * @return array<string, mixed>
+     */
+    private function fallbackGapRecord(CompareSubjectResult $subjectResult, string $reasonCode): array
+    {
+        $descriptor = $this->subjectResolver()->describeForCompare(
+            policyType: $subjectResult->subjectIdentity->subjectTypeKey,
+            subjectExternalId: $subjectResult->subjectIdentity->externalSubjectId,
+            subjectKey: $subjectResult->subjectIdentity->subjectKey,
+        );
+
+        $outcome = match ($reasonCode) {
+            'missing_current' => $this->subjectResolver()->missingExpectedRecord($descriptor),
+            'ambiguous_match' => $this->subjectResolver()->ambiguousMatch($descriptor),
+            default => $this->subjectResolver()->captureFailed($descriptor),
+        };
+
+        return array_merge($descriptor->toArray(), $outcome->toArray(), [
+            'reason_code' => $reasonCode,
+            'search_text' => strtolower(implode(' ', array_filter([
+                $subjectResult->subjectIdentity->subjectTypeKey,
+                $subjectResult->subjectIdentity->subjectKey,
+                $reasonCode,
+                $subjectResult->projection->operatorLabel,
+            ]))),
+        ]);
+    }
+
     /**
      * Load current inventory items keyed by "policy_type|subject_key".
      *
@@ -1069,13 +1358,13 @@ private function loadCurrentInventory(
                         'subject_external_id' => (string) $inventoryItem->external_id,
                         'subject_key' => $subjectKey,
                         'policy_type' => (string) $inventoryItem->policy_type,
-                        'meta_jsonb' => [
-                            'display_name' => $inventoryItem->display_name,
-                            'category' => $inventoryItem->category,
-                            'platform' => $inventoryItem->platform,
+                        'meta_jsonb' => array_replace($metaJsonb, [
+                            'display_name' => $metaJsonb['display_name'] ?? $inventoryItem->display_name,
+                            'category' => $metaJsonb['category'] ?? $inventoryItem->category,
+                            'platform' => $metaJsonb['platform'] ?? $inventoryItem->platform,
                             'is_built_in' => $metaJsonb['is_built_in'] ?? null,
                             'role_permission_count' => $metaJsonb['role_permission_count'] ?? null,
-                        ],
+                        ]),
                     ];
                 }
             });

apps/platform/app/Livewire/BaselineCompareEvidenceGapTable.php

@@ -94,13 +94,13 @@ public function table(Table $table): Table
                     ->sortable()
                     ->wrap()
                     ->toggleable(isToggledHiddenByDefault: true),
-                TextColumn::make('policy_type')
+                TextColumn::make('governed_subject_label')
                     ->label(__('baseline-compare.evidence_gap_policy_type'))
                     ->badge()
-                    ->formatStateUsing(TagBadgeRenderer::label(TagBadgeDomain::PolicyType))
-                    ->color(TagBadgeRenderer::color(TagBadgeDomain::PolicyType))
-                    ->icon(TagBadgeRenderer::icon(TagBadgeDomain::PolicyType))
-                    ->iconColor(TagBadgeRenderer::iconColor(TagBadgeDomain::PolicyType))
+                    ->formatStateUsing(fn (mixed $state): string => is_string($state) && trim($state) !== '' ? $state : 'Unknown governed subject')
+                    ->color(fn (mixed $state, Model $record): string => TagBadgeRenderer::spec(TagBadgeDomain::PolicyType, $record->getAttribute('policy_type'))->color)
+                    ->icon(fn (mixed $state, Model $record): ?string => TagBadgeRenderer::spec(TagBadgeDomain::PolicyType, $record->getAttribute('policy_type'))->icon)
+                    ->iconColor(fn (mixed $state, Model $record): ?string => TagBadgeRenderer::spec(TagBadgeDomain::PolicyType, $record->getAttribute('policy_type'))->iconColor)
                     ->searchable()
                     ->sortable()
                     ->wrap(),

apps/platform/app/Models/OperationRun.php

@@ -6,6 +6,7 @@
 use App\Support\OperationCatalog;
 use App\Support\OperationRunOutcome;
 use App\Support\OperationRunStatus;
+use App\Support\OperationTypeResolution;
 use App\Support\OperationRunType;
 use App\Support\Operations\OperationLifecyclePolicy;
 use App\Support\Operations\OperationRunFreshnessState;
@@ -291,6 +292,16 @@ public function inventoryCoverage(): ?InventoryCoverage
         return InventoryCoverage::fromContext($this->context);
     }
 
+    public function resolvedOperationType(): OperationTypeResolution
+    {
+        return OperationCatalog::resolve((string) $this->type);
+    }
+
+    public function canonicalOperationType(): string
+    {
+        return $this->resolvedOperationType()->canonical->canonicalCode;
+    }
+
     public function isGovernanceArtifactOperation(): bool
     {
         return OperationCatalog::isGovernanceArtifactOperation((string) $this->type);

apps/platform/app/Services/Baselines/BaselineCompareService.php

@@ -19,6 +19,9 @@
 use App\Support\Baselines\BaselineReasonCodes;
 use App\Support\Baselines\BaselineScope;
 use App\Support\Baselines\BaselineSupportCapabilityGuard;
+use App\Support\Baselines\Compare\CompareStrategyRegistry;
+use App\Support\Baselines\Compare\CompareStrategySelection;
+use App\Support\Baselines\Compare\StrategySelectionState;
 use App\Support\OperationRunType;
 use App\Support\ReasonTranslation\ReasonPresenter;
 use InvalidArgumentException;
@@ -31,6 +34,7 @@ public function __construct(
         private readonly BaselineSnapshotTruthResolver $snapshotTruthResolver,
         private readonly BaselineSupportCapabilityGuard $capabilityGuard,
         private readonly CapabilityResolver $capabilityResolver,
+        private readonly CompareStrategyRegistry $compareStrategyRegistry,
     ) {}
 
     /**
@@ -109,9 +113,7 @@ public function startCompareForProfile(
         $snapshotId = (int) $snapshot->getKey();
 
         try {
-            $profileScope = BaselineScope::fromJsonb(
-                is_array($profile->scope_jsonb) ? $profile->scope_jsonb : null,
-            );
+            $profileScope = $profile->normalizedScope();
             $overrideScope = $assignment->override_scope_jsonb !== null
                 ? BaselineScope::fromJsonb(
                     is_array($assignment->override_scope_jsonb) ? $assignment->override_scope_jsonb : null,
@@ -127,10 +129,10 @@ public function startCompareForProfile(
             return $this->failedStart(BaselineReasonCodes::COMPARE_INVALID_SCOPE);
         }
 
-        $eligibility = $effectiveScope->operationEligibility('compare', $this->capabilityGuard);
+        $selection = $this->compareStrategyRegistry->select($effectiveScope);
 
-        if (! $eligibility['ok']) {
-            return $this->failedStart(BaselineReasonCodes::COMPARE_UNSUPPORTED_SCOPE);
+        if (! $selection->isSupported()) {
+            return $this->failedStart($this->selectionFailureReasonCode($selection));
         }
 
         $captureMode = $profile->capture_mode instanceof BaselineCaptureMode
@@ -146,6 +148,9 @@ public function startCompareForProfile(
             'baseline_snapshot_id' => $snapshotId,
             'effective_scope' => $effectiveScope->toEffectiveScopeContext($this->capabilityGuard, 'compare'),
             'capture_mode' => $captureMode->value,
+            'baseline_compare' => [
+                'strategy' => $this->strategyContext($selection),
+            ],
         ];
 
         $run = $this->runs->ensureRunWithIdentity(
@@ -275,6 +280,36 @@ private function validatePreconditions(BaselineProfile $profile): ?string
         return null;
     }
 
+    private function selectionFailureReasonCode(CompareStrategySelection $selection): string
+    {
+        return match ($selection->selectionState) {
+            StrategySelectionState::Mixed => BaselineReasonCodes::COMPARE_MIXED_SCOPE,
+            default => BaselineReasonCodes::COMPARE_UNSUPPORTED_SCOPE,
+        };
+    }
+
+    /**
+     * @return array{
+     *   key: ?string,
+     *   selection_state: string,
+     *   matched_scope_entries: list<array<string, mixed>>,
+     *   rejected_scope_entries: list<array<string, mixed>>,
+     *   operator_reason: string,
+     *   diagnostics: array<string, mixed>
+     * }
+     */
+    private function strategyContext(CompareStrategySelection $selection): array
+    {
+        return [
+            'key' => $selection->strategyKey?->value,
+            'selection_state' => $selection->selectionState->value,
+            'matched_scope_entries' => $selection->matchedScopeEntries,
+            'rejected_scope_entries' => $selection->rejectedScopeEntries,
+            'operator_reason' => $selection->operatorReason,
+            'diagnostics' => $selection->diagnostics,
+        ];
+    }
+
     /**
      * @return array{ok: false, reason_code: string, reason_translation?: array<string, mixed>}
      */

apps/platform/app/Services/Baselines/SnapshotRendering/BaselineSnapshotPresenter.php

@@ -9,6 +9,7 @@
 use App\Support\Badges\BadgeCatalog;
 use App\Support\Badges\BadgeDomain;
 use App\Support\Badges\BadgeRenderer;
+use App\Support\Governance\PlatformSubjectDescriptorNormalizer;
 use App\Support\Inventory\InventoryPolicyTypeMeta;
 use App\Support\Ui\EnterpriseDetail\EnterpriseDetailBuilder;
 use App\Support\Ui\EnterpriseDetail\EnterpriseDetailPageData;
@@ -51,6 +52,8 @@ public function present(BaselineSnapshot $snapshot): RenderedSnapshot
             static fn (RenderedSnapshotGroup $group): array => [
                 'policyType' => $group->policyType,
                 'label' => $group->label,
+                'governedSubjectLabel' => data_get($group->subjectDescriptor, 'display_label', $group->label),
+                'subjectDescriptor' => $group->subjectDescriptor,
                 'itemCount' => $group->itemCount,
                 'fidelity' => $group->fidelity->value,
                 'gapCount' => $group->gapSummary->count,
@@ -166,7 +169,7 @@ public function presentEnterpriseDetail(BaselineSnapshot $snapshot, array $relat
                     title: 'Coverage summary',
                     view: 'filament.infolists.entries.baseline-snapshot-summary-table',
                     viewData: ['rows' => $rendered->summaryRows],
-                    emptyState: $factory->emptyState('No captured policy types are available in this snapshot.'),
+                    emptyState: $factory->emptyState('No captured governed subjects are available in this snapshot.'),
                 ),
                 $factory->viewSection(
                     id: 'related_context',
@@ -179,7 +182,7 @@ public function presentEnterpriseDetail(BaselineSnapshot $snapshot, array $relat
                 $factory->viewSection(
                     id: 'captured_policy_types',
                     kind: 'domain_detail',
-                    title: 'Captured policy types',
+                    title: 'Captured governed subjects',
                     view: 'filament.infolists.entries.baseline-snapshot-groups',
                     viewData: ['groups' => array_map(
                         static fn (RenderedSnapshotGroup $group): array => $group->toArray(),
@@ -250,7 +253,8 @@ private function presentGroup(string $policyType, Collection $items): RenderedSn
         $renderer = $this->registry->rendererFor($policyType);
         $fallbackRenderer = $this->registry->fallbackRenderer();
         $renderingError = null;
-        $technicalPayload = $this->technicalPayload($items);
+        $subjectDescriptor = $this->subjectDescriptor($policyType);
+        $technicalPayload = $this->technicalPayload($items) + ['subject_descriptor' => $subjectDescriptor];
 
         try {
             $renderedItems = $items
@@ -261,7 +265,7 @@ private function presentGroup(string $policyType, Collection $items): RenderedSn
                 ->map(fn (BaselineSnapshotItem $item): RenderedSnapshotItem => $fallbackRenderer->render($item))
                 ->all();
 
-            $renderingError = 'Structured rendering failed for this policy type. Fallback metadata is shown instead.';
+            $renderingError = 'Structured rendering failed for this governed subject family. Fallback metadata is shown instead.';
         }
 
         /** @var array<int, RenderedSnapshotItem> $renderedItems */
@@ -299,6 +303,7 @@ private function presentGroup(string $policyType, Collection $items): RenderedSn
             coverageHint: $coverageHint,
             capturedAt: is_string($capturedAt) ? $capturedAt : null,
             technicalPayload: $technicalPayload,
+            subjectDescriptor: $subjectDescriptor,
         );
     }
 
@@ -404,9 +409,28 @@ private function currentTruthPresentation(ArtifactTruthEnvelope $truth): array
 
     private function typeLabel(string $policyType): string
     {
-        return InventoryPolicyTypeMeta::baselineCompareLabel($policyType)
+        return (string) (data_get($this->subjectDescriptor($policyType), 'display_label')
+            ?? InventoryPolicyTypeMeta::baselineCompareLabel($policyType)
             ?? InventoryPolicyTypeMeta::label($policyType)
-            ?? Str::headline($policyType);
+            ?? Str::headline($policyType));
+    }
+
+    /**
+     * @return array<string, mixed>
+     */
+    private function subjectDescriptor(string $policyType): array
+    {
+        static $cache = [];
+
+        if (array_key_exists($policyType, $cache)) {
+            return $cache[$policyType];
+        }
+
+        $result = app(PlatformSubjectDescriptorNormalizer::class)->fromArray([
+            'policy_type' => $policyType,
+        ], 'baseline_snapshot');
+
+        return $cache[$policyType] = $result->descriptor->toArray();
     }
 
     private function formatTimestamp(?string $value): string

apps/platform/app/Services/Baselines/SnapshotRendering/RenderedSnapshotGroup.php

@@ -9,6 +9,7 @@
     /**
      * @param  array<int, RenderedSnapshotItem>  $items
      * @param  array<string, mixed>  $technicalPayload
+     * @param  array<string, mixed>  $subjectDescriptor
      */
     public function __construct(
         public string $policyType,
@@ -22,6 +23,7 @@ public function __construct(
         public ?string $coverageHint = null,
         public ?string $capturedAt = null,
         public array $technicalPayload = [],
+        public array $subjectDescriptor = [],
     ) {}
 
     /**
@@ -46,7 +48,8 @@ public function __construct(
      *   renderingError: ?string,
      *   coverageHint: ?string,
      *   capturedAt: ?string,
-     *   technicalPayload: array<string, mixed>
+    *   technicalPayload: array<string, mixed>,
+    *   subjectDescriptor: array<string, mixed>
      * }
      */
     public function toArray(): array
@@ -66,6 +69,7 @@ public function toArray(): array
             'coverageHint' => $this->coverageHint,
             'capturedAt' => $this->capturedAt,
             'technicalPayload' => $this->technicalPayload,
+            'subjectDescriptor' => $this->subjectDescriptor,
         ];
     }
 }

apps/platform/app/Support/Baselines/BaselineCompareEvidenceGapDetails.php

@@ -5,6 +5,7 @@
 namespace App\Support\Baselines;
 
 use App\Models\OperationRun;
+use App\Support\Governance\PlatformSubjectDescriptorNormalizer;
 use Illuminate\Support\Str;
 
 final class BaselineCompareEvidenceGapDetails
@@ -151,6 +152,7 @@ public static function diagnosticsPayload(array $baselineCompare): array
             'subjects_total' => self::intOrNull($baselineCompare['subjects_total'] ?? null),
             'resume_token' => self::stringOrNull($baselineCompare['resume_token'] ?? null),
             'fidelity' => self::stringOrNull($baselineCompare['fidelity'] ?? null),
+            'strategy' => is_array($baselineCompare['strategy'] ?? null) ? $baselineCompare['strategy'] : null,
             'coverage' => is_array($baselineCompare['coverage'] ?? null) ? $baselineCompare['coverage'] : null,
             'evidence_capture' => is_array($baselineCompare['evidence_capture'] ?? null) ? $baselineCompare['evidence_capture'] : null,
             'evidence_gaps' => is_array($baselineCompare['evidence_gaps'] ?? null) ? $baselineCompare['evidence_gaps'] : null,
@@ -332,6 +334,8 @@ public static function tableRows(array $buckets): array
                     'reason_code' => $reasonCode,
                     'reason_label' => self::reasonLabel($reasonCode),
                     'policy_type' => $policyType,
+                    'governed_subject_label' => (string) ($row['governed_subject_label'] ?? self::governedSubjectLabel($policyType)),
+                    'governed_subject' => is_array($row['governed_subject'] ?? null) ? $row['governed_subject'] : self::subjectDescriptor($policyType),
                     'subject_key' => $subjectKey,
                     'subject_class' => $subjectClass,
                     'subject_class_label' => self::subjectClassLabel($subjectClass),
@@ -372,10 +376,11 @@ public static function reasonFilterOptions(array $rows): array
     public static function policyTypeFilterOptions(array $rows): array
     {
         return collect($rows)
-            ->pluck('policy_type')
-            ->filter(fn (mixed $value): bool => is_string($value) && trim($value) !== '')
-            ->mapWithKeys(fn (string $value): array => [$value => $value])
-            ->sortKeysUsing('strnatcasecmp')
+            ->filter(fn (array $row): bool => filled($row['policy_type'] ?? null))
+            ->mapWithKeys(fn (array $row): array => [
+                (string) $row['policy_type'] => (string) ($row['governed_subject_label'] ?? $row['policy_type']),
+            ])
+            ->sortBy(fn (string $label): string => Str::lower($label))
             ->all();
     }
 
@@ -658,16 +663,20 @@ private static function projectSubjectRow(array $subject): array
         $subjectClass = (string) $subject['subject_class'];
         $resolutionOutcome = (string) $subject['resolution_outcome'];
         $operatorActionCategory = (string) $subject['operator_action_category'];
+        $policyType = (string) ($subject['policy_type'] ?? '');
 
         return array_merge($subject, [
             'reason_label' => self::reasonLabel($reasonCode),
+            'governed_subject' => self::subjectDescriptor($policyType),
+            'governed_subject_label' => self::governedSubjectLabel($policyType),
             'subject_class_label' => self::subjectClassLabel($subjectClass),
             'resolution_outcome_label' => self::resolutionOutcomeLabel($resolutionOutcome),
             'operator_action_category_label' => self::operatorActionCategoryLabel($operatorActionCategory),
             'search_text' => Str::lower(trim(implode(' ', array_filter([
                 $reasonCode,
                 self::reasonLabel($reasonCode),
-                (string) ($subject['policy_type'] ?? ''),
+                $policyType,
+                self::governedSubjectLabel($policyType),
                 (string) ($subject['subject_key'] ?? ''),
                 $subjectClass,
                 self::subjectClassLabel($subjectClass),
@@ -681,6 +690,29 @@ private static function projectSubjectRow(array $subject): array
         ]);
     }
 
+    /**
+     * @return array<string, mixed>
+     */
+    private static function subjectDescriptor(string $policyType): array
+    {
+        static $cache = [];
+
+        if (array_key_exists($policyType, $cache)) {
+            return $cache[$policyType];
+        }
+
+        $result = app(PlatformSubjectDescriptorNormalizer::class)->fromArray([
+            'policy_type' => $policyType,
+        ], 'baseline_compare');
+
+        return $cache[$policyType] = $result->descriptor->toArray();
+    }
+
+    private static function governedSubjectLabel(string $policyType): string
+    {
+        return (string) (data_get(self::subjectDescriptor($policyType), 'display_label') ?: $policyType);
+    }
+
     private static function stringOrNull(mixed $value): ?string
     {
         if (! is_string($value)) {

apps/platform/app/Support/Baselines/BaselineCompareExplanationRegistry.php

@@ -128,7 +128,7 @@ public function forStats(BaselineCompareStats $stats): OperatorExplanationPatter
             $stats->state === 'idle' => 'No compare run has produced a result yet for this tenant.',
             $isFailed => 'The last compare run did not finish cleanly, so current counts should not be treated as decision-grade.',
             $stats->coverageStatus === 'unproven' => 'Coverage proof was unavailable, so suppressed output is possible even when the findings count is zero.',
-            $stats->uncoveredTypes !== [] => 'One or more in-scope policy types were not fully covered in this compare run.',
+            $stats->uncoveredTypes !== [] => 'One or more in-scope governed subjects were not fully covered in this compare run.',
             $hasEvidenceGaps => 'Evidence gaps limited the quality of the visible result for some subjects.',
             $isInProgress => 'Counts will become decision-grade after the compare run finishes.',
             in_array($family, [ExplanationFamily::MissingInput, ExplanationFamily::BlockedPrerequisite, ExplanationFamily::Unavailable], true) => $reason?->shortExplanation ?? 'The compare inputs were not complete enough to produce a normal result.',

apps/platform/app/Support/Baselines/BaselineCompareMatrixBuilder.php

@@ -17,6 +17,7 @@
 use App\Support\Auth\Capabilities;
 use App\Support\Badges\BadgeCatalog;
 use App\Support\Badges\BadgeDomain;
+use App\Support\Governance\PlatformSubjectDescriptorNormalizer;
 use App\Support\Inventory\InventoryPolicyTypeMeta;
 use App\Support\OperationRunOutcome;
 use App\Support\OperationRunStatus;
@@ -81,8 +82,8 @@ public function build(BaselineProfile $profile, User $user, array $filters = [])
             ->filter(static fn (mixed $type): bool => is_string($type) && trim($type) !== '')
             ->unique()
             ->sort()
-            ->mapWithKeys(static fn (string $type): array => [
-                $type => InventoryPolicyTypeMeta::label($type) ?? $type,
+            ->mapWithKeys(fn (string $type): array => [
+                $type => $this->governedSubjectLabel($type),
             ])
             ->all();
 
@@ -118,7 +119,7 @@ public function build(BaselineProfile $profile, User $user, array $filters = [])
             ],
             'subjectSortOptions' => [
                 'deviation_breadth' => 'Deviation breadth',
-                'policy_type' => 'Policy type',
+                'policy_type' => 'Governed subject',
                 'display_name' => 'Display name',
             ],
             'stateLegend' => $this->legendSpecs(BadgeDomain::BaselineCompareMatrixState, [
@@ -209,6 +210,8 @@ public function build(BaselineProfile $profile, User $user, array $filters = [])
             $subject = [
                 'subjectKey' => $subjectKey,
                 'policyType' => (string) $item->policy_type,
+                'governedSubjectLabel' => $this->governedSubjectLabel((string) $item->policy_type),
+                'subjectDescriptor' => $this->subjectDescriptor((string) $item->policy_type),
                 'displayName' => $this->subjectDisplayName($item),
                 'baselineExternalId' => is_string($item->subject_external_id) ? $item->subject_external_id : null,
             ];
@@ -572,7 +575,7 @@ private function reasonSummary(string $state, ?string $reasonCode, bool $policyT
             'stale_result' => 'Refresh recommended before acting on this result.',
             'not_compared' => $policyTypeCovered
                 ? 'No completed compare result is available yet.'
-                : 'Policy type coverage was not proven in the latest compare run.',
+                : 'Governed subject coverage was not proven in the latest compare run.',
             default => null,
         };
     }
@@ -642,6 +645,8 @@ private function subjectSummary(array $subject, array $cells): array
         return [
             'subjectKey' => $subject['subjectKey'],
             'policyType' => $subject['policyType'],
+            'governedSubjectLabel' => $subject['governedSubjectLabel'] ?? $this->governedSubjectLabel((string) $subject['policyType']),
+            'subjectDescriptor' => $subject['subjectDescriptor'] ?? $this->subjectDescriptor((string) $subject['policyType']),
             'displayName' => $subject['displayName'],
             'baselineExternalId' => $subject['baselineExternalId'],
             'deviationBreadth' => $this->countStates($cells, ['differ', 'missing']),
@@ -809,8 +814,13 @@ private function sortRows(array $rows, string $sort): array
             $rightSubject = $right['subject'] ?? [];
 
             return match ($sort) {
-                'policy_type' => [(string) ($leftSubject['policyType'] ?? ''), Str::lower((string) ($leftSubject['displayName'] ?? ''))]
-                    <=> [(string) ($rightSubject['policyType'] ?? ''), Str::lower((string) ($rightSubject['displayName'] ?? ''))],
+                'policy_type' => [
+                    Str::lower((string) ($leftSubject['governedSubjectLabel'] ?? $leftSubject['policyType'] ?? '')),
+                    Str::lower((string) ($leftSubject['displayName'] ?? '')),
+                ] <=> [
+                    Str::lower((string) ($rightSubject['governedSubjectLabel'] ?? $rightSubject['policyType'] ?? '')),
+                    Str::lower((string) ($rightSubject['displayName'] ?? '')),
+                ],
                 'display_name' => [Str::lower((string) ($leftSubject['displayName'] ?? '')), (string) ($leftSubject['subjectKey'] ?? '')]
                     <=> [Str::lower((string) ($rightSubject['displayName'] ?? '')), (string) ($rightSubject['subjectKey'] ?? '')],
                 default => [
@@ -914,6 +924,8 @@ private function compactResults(array $rows, array $tenantSummaries): array
                 'subjectKey' => (string) ($subject['subjectKey'] ?? ''),
                 'displayName' => $subject['displayName'] ?? $subject['subjectKey'] ?? 'Subject',
                 'policyType' => (string) ($subject['policyType'] ?? ''),
+                'governedSubjectLabel' => (string) ($subject['governedSubjectLabel'] ?? $this->governedSubjectLabel((string) ($subject['policyType'] ?? ''))),
+                'subjectDescriptor' => $subject['subjectDescriptor'] ?? $this->subjectDescriptor((string) ($subject['policyType'] ?? '')),
                 'baselineExternalId' => $subject['baselineExternalId'] ?? null,
                 'deviationBreadth' => (int) ($subject['deviationBreadth'] ?? 0),
                 'missingBreadth' => (int) ($subject['missingBreadth'] ?? 0),
@@ -974,7 +986,7 @@ private function emptyState(
         if ($renderedRowsCount === 0) {
             return [
                 'title' => 'No rows match the current filters',
-                'body' => 'Adjust the policy type, state, or severity filters to broaden the matrix view.',
+                'body' => 'Adjust the governed subject, state, or severity filters to broaden the matrix view.',
             ];
         }
 
@@ -1002,4 +1014,31 @@ static function (string $value) use ($domain): array {
             $values,
         );
     }
+
+    private function governedSubjectLabel(string $policyType): string
+    {
+        return (string) data_get(
+            $this->subjectDescriptor($policyType),
+            'display_label',
+            InventoryPolicyTypeMeta::label($policyType) ?? Str::headline($policyType),
+        );
+    }
+
+    /**
+     * @return array<string, mixed>
+     */
+    private function subjectDescriptor(string $policyType): array
+    {
+        static $cache = [];
+
+        if (array_key_exists($policyType, $cache)) {
+            return $cache[$policyType];
+        }
+
+        $result = app(PlatformSubjectDescriptorNormalizer::class)->fromArray([
+            'policy_type' => $policyType,
+        ], 'baseline_compare_matrix');
+
+        return $cache[$policyType] = $result->descriptor->toArray();
+    }
 }

apps/platform/app/Support/Baselines/BaselineCompareReasonCode.php

@@ -12,6 +12,9 @@ enum BaselineCompareReasonCode: string
     case NoSubjectsInScope = 'no_subjects_in_scope';
     case CoverageUnproven = 'coverage_unproven';
     case EvidenceCaptureIncomplete = 'evidence_capture_incomplete';
+    case UnsupportedSubjects = 'unsupported_subjects';
+    case AmbiguousSubjects = 'ambiguous_subjects';
+    case StrategyFailed = 'strategy_failed';
     case RolloutDisabled = 'rollout_disabled';
     case NoDriftDetected = 'no_drift_detected';
     case OverdueFindingsRemain = 'overdue_findings_remain';
@@ -24,6 +27,9 @@ public function message(): string
             self::NoSubjectsInScope => 'No subjects were in scope for this comparison.',
             self::CoverageUnproven => 'Coverage proof was missing or incomplete, so some findings were suppressed for safety.',
             self::EvidenceCaptureIncomplete => 'Evidence capture was incomplete, so some drift evaluation may have been suppressed.',
+            self::UnsupportedSubjects => 'One or more in-scope subjects could not be compared by the selected strategy.',
+            self::AmbiguousSubjects => 'One or more in-scope subjects could not be compared because identity matching stayed ambiguous.',
+            self::StrategyFailed => 'One or more in-scope subjects failed during strategy processing, so the compare result is incomplete.',
             self::RolloutDisabled => 'Full-content baseline compare is currently disabled by rollout configuration.',
             self::NoDriftDetected => 'No drift was detected for in-scope subjects.',
             self::OverdueFindingsRemain => 'Overdue findings still need action even though the latest compare did not produce new drift.',
@@ -38,10 +44,13 @@ public function explanationFamily(): ExplanationFamily
             self::NoDriftDetected => ExplanationFamily::NoIssuesDetected,
             self::CoverageUnproven,
             self::EvidenceCaptureIncomplete,
+            self::UnsupportedSubjects,
+            self::AmbiguousSubjects,
             self::RolloutDisabled,
             self::OverdueFindingsRemain,
             self::GovernanceExpiring,
             self::GovernanceLapsed => ExplanationFamily::CompletedButLimited,
+            self::StrategyFailed => ExplanationFamily::BlockedPrerequisite,
             self::NoSubjectsInScope => ExplanationFamily::MissingInput,
         };
     }
@@ -52,9 +61,12 @@ public function trustworthinessLevel(): TrustworthinessLevel
             self::NoDriftDetected => TrustworthinessLevel::Trustworthy,
             self::CoverageUnproven,
             self::EvidenceCaptureIncomplete,
+            self::UnsupportedSubjects,
+            self::AmbiguousSubjects,
             self::OverdueFindingsRemain,
             self::GovernanceExpiring,
             self::GovernanceLapsed => TrustworthinessLevel::LimitedConfidence,
+            self::StrategyFailed,
             self::RolloutDisabled,
             self::NoSubjectsInScope => TrustworthinessLevel::Unusable,
         };
@@ -66,9 +78,12 @@ public function absencePattern(): ?string
             self::NoDriftDetected => 'true_no_result',
             self::CoverageUnproven,
             self::EvidenceCaptureIncomplete,
+            self::UnsupportedSubjects,
+            self::AmbiguousSubjects,
             self::OverdueFindingsRemain,
             self::GovernanceExpiring,
             self::GovernanceLapsed => 'suppressed_output',
+            self::StrategyFailed,
             self::RolloutDisabled => 'blocked_prerequisite',
             self::NoSubjectsInScope => 'missing_input',
         };

apps/platform/app/Support/Baselines/BaselineCompareStats.php

@@ -122,9 +122,7 @@ public static function forTenant(?Tenant $tenant): self
         $snapshotReasonMessage = self::missingSnapshotMessage($snapshotReasonCode);
 
         try {
-            $profileScope = BaselineScope::fromJsonb(
-                is_array($profile->scope_jsonb) ? $profile->scope_jsonb : null,
-            );
+            $profileScope = $profile->normalizedScope();
             $overrideScope = $assignment->override_scope_jsonb !== null
                 ? BaselineScope::fromJsonb(
                     is_array($assignment->override_scope_jsonb) ? $assignment->override_scope_jsonb : null,

apps/platform/app/Support/Baselines/BaselineReasonCodes.php

@@ -54,6 +54,8 @@ final class BaselineReasonCodes
 
     public const string COMPARE_UNSUPPORTED_SCOPE = 'baseline.compare.unsupported_scope';
 
+    public const string COMPARE_MIXED_SCOPE = 'baseline.compare.mixed_scope';
+
     public const string COMPARE_SNAPSHOT_BUILDING = 'baseline.compare.snapshot_building';
 
     public const string COMPARE_SNAPSHOT_INCOMPLETE = 'baseline.compare.snapshot_incomplete';
@@ -87,6 +89,7 @@ public static function all(): array
             self::COMPARE_ROLLOUT_DISABLED,
             self::COMPARE_INVALID_SCOPE,
             self::COMPARE_UNSUPPORTED_SCOPE,
+            self::COMPARE_MIXED_SCOPE,
             self::COMPARE_SNAPSHOT_BUILDING,
             self::COMPARE_SNAPSHOT_INCOMPLETE,
             self::COMPARE_SNAPSHOT_SUPERSEDED,
@@ -121,6 +124,7 @@ public static function trustImpact(?string $reasonCode): ?string
             self::COMPARE_SNAPSHOT_SUPERSEDED,
             self::COMPARE_INVALID_SCOPE,
             self::COMPARE_UNSUPPORTED_SCOPE,
+            self::COMPARE_MIXED_SCOPE,
             self::CAPTURE_MISSING_SOURCE_TENANT,
             self::CAPTURE_PROFILE_NOT_ACTIVE,
             self::CAPTURE_INVALID_SCOPE,
@@ -150,6 +154,7 @@ public static function absencePattern(?string $reasonCode): ?string
             self::COMPARE_INVALID_SNAPSHOT,
             self::COMPARE_INVALID_SCOPE,
             self::COMPARE_UNSUPPORTED_SCOPE,
+            self::COMPARE_MIXED_SCOPE,
             self::COMPARE_ROLLOUT_DISABLED,
             self::SNAPSHOT_SUPERSEDED,
             self::COMPARE_SNAPSHOT_SUPERSEDED => 'blocked_prerequisite',

apps/platform/app/Support/Baselines/BaselineScope.php

@@ -7,6 +7,7 @@
 use App\Support\Governance\GovernanceDomainKey;
 use App\Support\Governance\GovernanceSubjectClass;
 use App\Support\Governance\GovernanceSubjectTaxonomyRegistry;
+use App\Support\Governance\PlatformSubjectDescriptorNormalizer;
 use App\Support\Inventory\InventoryPolicyTypeMeta;
 use InvalidArgumentException;
 
@@ -187,9 +188,19 @@ public function allTypes(): array
     {
         $expanded = $this->expandDefaults();
 
+        $canonicalTypeKeys = [];
+
+        foreach ($expanded->entries as $entry) {
+            $canonicalTypeKeys = array_merge(
+                $canonicalTypeKeys,
+                is_array($entry['subject_type_keys'] ?? null) ? $entry['subject_type_keys'] : [],
+            );
+        }
+
         return self::uniqueSorted(array_merge(
             $expanded->policyTypes,
             $expanded->foundationTypes,
+            $canonicalTypeKeys,
         ));
     }
 
@@ -293,6 +304,16 @@ public function summaryGroups(?GovernanceSubjectTaxonomyRegistry $registry = nul
         return $groups;
     }
 
+    /**
+     * @return list<array<string, mixed>>
+     */
+    public function subjectDescriptors(?PlatformSubjectDescriptorNormalizer $normalizer = null): array
+    {
+        $normalizer ??= app(PlatformSubjectDescriptorNormalizer::class);
+
+        return $normalizer->descriptorsForScopeEntries($this->entries);
+    }
+
     /**
      * Effective scope payload for OperationRun.context.
      *
@@ -301,7 +322,7 @@ public function summaryGroups(?GovernanceSubjectTaxonomyRegistry $registry = nul
     public function toEffectiveScopeContext(?BaselineSupportCapabilityGuard $guard = null, ?string $operation = null): array
     {
         $expanded = $this->expandDefaults();
-        $allTypes = self::uniqueSorted(array_merge($expanded->policyTypes, $expanded->foundationTypes));
+        $allTypes = $expanded->allTypes();
 
         $context = [
             'canonical_scope' => $expanded->toStoredJsonb(),
@@ -311,6 +332,7 @@ public function toEffectiveScopeContext(?BaselineSupportCapabilityGuard $guard =
             'all_types' => $allTypes,
             'selected_type_keys' => $allTypes,
             'foundations_included' => $expanded->foundationTypes !== [],
+            'governed_subjects' => $expanded->subjectDescriptors(),
         ];
 
         if (! is_string($operation) || $operation === '') {

apps/platform/app/Support/Baselines/Compare/CompareFindingCandidate.php

@@ -0,0 +1,46 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Support\Baselines\Compare;
+
+use InvalidArgumentException;
+
+final class CompareFindingCandidate
+{
+    /**
+     * @param  array<string, mixed>  $fingerprintBasis
+     * @param  array<string, mixed>  $evidencePayload
+     */
+    public function __construct(
+        public readonly string $changeType,
+        public readonly string $severity,
+        public readonly array $fingerprintBasis,
+        public readonly array $evidencePayload,
+        public readonly bool $autoCloseEligible = true,
+    ) {
+        if (trim($this->changeType) === '' || trim($this->severity) === '') {
+            throw new InvalidArgumentException('Compare finding candidates require non-empty change type and severity values.');
+        }
+    }
+
+    /**
+     * @return array{
+     *   change_type: string,
+     *   severity: string,
+     *   fingerprint_basis: array<string, mixed>,
+     *   evidence_payload: array<string, mixed>,
+     *   auto_close_eligible: bool
+     * }
+     */
+    public function toArray(): array
+    {
+        return [
+            'change_type' => $this->changeType,
+            'severity' => $this->severity,
+            'fingerprint_basis' => $this->fingerprintBasis,
+            'evidence_payload' => $this->evidencePayload,
+            'auto_close_eligible' => $this->autoCloseEligible,
+        ];
+    }
+}

apps/platform/app/Support/Baselines/Compare/CompareOrchestrationContext.php

@@ -0,0 +1,82 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Support\Baselines\Compare;
+
+use InvalidArgumentException;
+
+final class CompareOrchestrationContext
+{
+    /**
+     * @param  array<string, mixed>  $normalizedScope
+     * @param  array<string, mixed>  $coverageContext
+     * @param  array<string, mixed>  $launchContext
+     */
+    public function __construct(
+        public readonly int $workspaceId,
+        public readonly int $tenantId,
+        public readonly int $baselineProfileId,
+        public readonly int $baselineSnapshotId,
+        public readonly int $operationRunId,
+        public readonly array $normalizedScope,
+        public readonly CompareStrategySelection $strategySelection,
+        public readonly array $coverageContext = [],
+        public readonly array $launchContext = [],
+    ) {
+        if ($this->workspaceId <= 0 || $this->tenantId <= 0 || $this->baselineProfileId <= 0 || $this->baselineSnapshotId <= 0 || $this->operationRunId <= 0) {
+            throw new InvalidArgumentException('Compare orchestration contexts require positive workspace, tenant, profile, snapshot, and operation run identifiers.');
+        }
+    }
+
+    public function strategyKey(): CompareStrategyKey
+    {
+        if (! $this->strategySelection->strategyKey instanceof CompareStrategyKey) {
+            throw new InvalidArgumentException('Compare orchestration context requires a supported strategy selection before execution.');
+        }
+
+        return $this->strategySelection->strategyKey;
+    }
+
+    public function inventorySyncRunId(): ?int
+    {
+        $value = $this->coverageContext['inventory_sync_run_id'] ?? $this->launchContext['inventory_sync_run_id'] ?? null;
+
+        return is_numeric($value) ? (int) $value : null;
+    }
+
+    /**
+     * @return array{
+     *   workspace_id: int,
+     *   tenant_id: int,
+     *   baseline_profile_id: int,
+     *   baseline_snapshot_id: int,
+     *   operation_run_id: int,
+     *   normalized_scope: array<string, mixed>,
+     *   strategy_selection: array{
+     *     selection_state: string,
+     *     strategy_key: ?string,
+     *     matched_scope_entries: list<array<string, mixed>>,
+     *     rejected_scope_entries: list<array<string, mixed>>,
+     *     operator_reason: string,
+     *     diagnostics: array<string, mixed>
+     *   },
+     *   coverage_context: array<string, mixed>,
+     *   launch_context: array<string, mixed>
+     * }
+     */
+    public function toArray(): array
+    {
+        return [
+            'workspace_id' => $this->workspaceId,
+            'tenant_id' => $this->tenantId,
+            'baseline_profile_id' => $this->baselineProfileId,
+            'baseline_snapshot_id' => $this->baselineSnapshotId,
+            'operation_run_id' => $this->operationRunId,
+            'normalized_scope' => $this->normalizedScope,
+            'strategy_selection' => $this->strategySelection->toArray(),
+            'coverage_context' => $this->coverageContext,
+            'launch_context' => $this->launchContext,
+        ];
+    }
+}

apps/platform/app/Support/Baselines/Compare/CompareState.php

@@ -0,0 +1,15 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Support\Baselines\Compare;
+
+enum CompareState: string
+{
+    case NoDrift = 'no_drift';
+    case Drift = 'drift';
+    case Unsupported = 'unsupported';
+    case Incomplete = 'incomplete';
+    case Ambiguous = 'ambiguous';
+    case Failed = 'failed';
+}

apps/platform/app/Support/Baselines/Compare/CompareStrategy.php

@@ -0,0 +1,34 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Support\Baselines\Compare;
+
+use App\Models\Tenant;
+use App\Services\Baselines\Evidence\ResolvedEvidence;
+
+interface CompareStrategy
+{
+    public function key(): CompareStrategyKey;
+
+    /**
+     * @return list<CompareStrategyCapability>
+     */
+    public function capabilities(): array;
+
+    /**
+     * @param  array<string, array{subject_type: string, subject_external_id: string, subject_key: string, policy_type: string, baseline_hash: string, meta_jsonb: array<string, mixed>}>  $baselineItems
+     * @param  array<string, array{subject_external_id: string, subject_key: string, policy_type: string, meta_jsonb: array<string, mixed>}>  $currentItems
+     * @param  array<string, ResolvedEvidence|null>  $resolvedCurrentEvidence
+     * @param  array<string, string>  $severityMapping
+     * @return array{subject_results: list<CompareSubjectResult>, diagnostics: array<string, mixed>}
+     */
+    public function compare(
+        CompareOrchestrationContext $context,
+        Tenant $tenant,
+        array $baselineItems,
+        array $currentItems,
+        array $resolvedCurrentEvidence,
+        array $severityMapping,
+    ): array;
+}

apps/platform/app/Support/Baselines/Compare/CompareStrategyCapability.php

@@ -0,0 +1,84 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Support\Baselines\Compare;
+
+use InvalidArgumentException;
+
+final class CompareStrategyCapability
+{
+    /**
+     * @param  list<string>  $domainKeys
+     * @param  list<string>  $subjectClasses
+     * @param  list<string>|'all'  $subjectTypeKeys
+     */
+    public function __construct(
+        public readonly CompareStrategyKey $strategyKey,
+        public readonly array $domainKeys,
+        public readonly array $subjectClasses,
+        public readonly array|string $subjectTypeKeys = 'all',
+        public readonly bool $compareSupported = true,
+        public readonly bool $active = true,
+    ) {
+        if ($this->domainKeys === [] || $this->subjectClasses === []) {
+            throw new InvalidArgumentException('Compare strategy capabilities require at least one domain key and one subject class.');
+        }
+
+        if ($this->subjectTypeKeys !== 'all' && $this->subjectTypeKeys === []) {
+            throw new InvalidArgumentException('Compare strategy capabilities must either support all subject type keys or at least one explicit subject type key.');
+        }
+    }
+
+    /**
+     * @param  array{domain_key?: mixed, subject_class?: mixed, subject_type_keys?: mixed}  $entry
+     */
+    public function supportsEntry(array $entry): bool
+    {
+        if (! $this->active || ! $this->compareSupported) {
+            return false;
+        }
+
+        $domainKey = is_string($entry['domain_key'] ?? null) ? trim((string) $entry['domain_key']) : '';
+        $subjectClass = is_string($entry['subject_class'] ?? null) ? trim((string) $entry['subject_class']) : '';
+        $subjectTypeKeys = is_array($entry['subject_type_keys'] ?? null)
+            ? array_values(array_filter($entry['subject_type_keys'], 'is_string'))
+            : [];
+
+        if ($domainKey === '' || $subjectClass === '' || $subjectTypeKeys === []) {
+            return false;
+        }
+
+        if (! in_array($domainKey, $this->domainKeys, true) || ! in_array($subjectClass, $this->subjectClasses, true)) {
+            return false;
+        }
+
+        if ($this->subjectTypeKeys === 'all') {
+            return true;
+        }
+
+        return array_diff($subjectTypeKeys, $this->subjectTypeKeys) === [];
+    }
+
+    /**
+     * @return array{
+     *   strategy_key: string,
+     *   domain_keys: list<string>,
+     *   subject_classes: list<string>,
+     *   subject_type_keys: list<string>|'all',
+     *   compare_supported: bool,
+     *   active: bool
+     * }
+     */
+    public function toArray(): array
+    {
+        return [
+            'strategy_key' => $this->strategyKey->value,
+            'domain_keys' => $this->domainKeys,
+            'subject_classes' => $this->subjectClasses,
+            'subject_type_keys' => $this->subjectTypeKeys,
+            'compare_supported' => $this->compareSupported,
+            'active' => $this->active,
+        ];
+    }
+}

apps/platform/app/Support/Baselines/Compare/CompareStrategyKey.php

@@ -0,0 +1,44 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Support\Baselines\Compare;
+
+use InvalidArgumentException;
+use Stringable;
+
+final class CompareStrategyKey implements Stringable
+{
+    public readonly string $value;
+
+    public function __construct(string $value)
+    {
+        $normalized = trim(mb_strtolower($value));
+
+        if ($normalized === '' || ! preg_match('/^[a-z0-9_]+$/', $normalized)) {
+            throw new InvalidArgumentException('Compare strategy keys must be non-empty lowercase snake_case strings.');
+        }
+
+        $this->value = $normalized;
+    }
+
+    public static function from(self|string $value): self
+    {
+        return $value instanceof self ? $value : new self($value);
+    }
+
+    public static function intunePolicy(): self
+    {
+        return new self('intune_policy');
+    }
+
+    public function equals(self|string $other): bool
+    {
+        return $this->value === self::from($other)->value;
+    }
+
+    public function __toString(): string
+    {
+        return $this->value;
+    }
+}

apps/platform/app/Support/Baselines/Compare/CompareStrategyRegistry.php

@@ -0,0 +1,202 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Support\Baselines\Compare;
+
+use App\Support\Baselines\BaselineScope;
+use App\Support\Governance\GovernanceDomainKey;
+use App\Support\Governance\GovernanceSubjectClass;
+use InvalidArgumentException;
+
+final class CompareStrategyRegistry
+{
+    /**
+     * @param  list<CompareStrategy>  $strategies
+     */
+    public function __construct(
+        private readonly array $strategies = [],
+    ) {}
+
+    /**
+     * @return list<CompareStrategy>
+     */
+    public function all(): array
+    {
+        if ($this->strategies !== []) {
+            return $this->strategies;
+        }
+
+        return [app(IntuneCompareStrategy::class)];
+    }
+
+    public function find(CompareStrategyKey|string|null $strategyKey): ?CompareStrategy
+    {
+        if ($strategyKey === null) {
+            return null;
+        }
+
+        $normalizedKey = CompareStrategyKey::from($strategyKey);
+
+        foreach ($this->all() as $strategy) {
+            if ($strategy->key()->equals($normalizedKey)) {
+                return $strategy;
+            }
+        }
+
+        return null;
+    }
+
+    public function resolve(CompareStrategyKey|string $strategyKey): CompareStrategy
+    {
+        $strategy = $this->find($strategyKey);
+
+        if ($strategy instanceof CompareStrategy) {
+            return $strategy;
+        }
+
+        throw new InvalidArgumentException('Unknown compare strategy ['.CompareStrategyKey::from($strategyKey)->value.'].');
+    }
+
+    public function select(BaselineScope $scope): CompareStrategySelection
+    {
+        $entries = $this->entriesForScope($scope);
+
+        if ($entries === []) {
+            return CompareStrategySelection::unsupported(
+                matchedScopeEntries: [],
+                rejectedScopeEntries: [],
+                diagnostics: [],
+                operatorReason: 'No governed subjects were selected for compare.',
+            );
+        }
+
+        $matchedScopeEntries = [];
+        $rejectedScopeEntries = [];
+        $matchedStrategyKeys = [];
+        $entryMatches = [];
+
+        foreach ($entries as $entry) {
+            $matchingKeys = $this->matchingStrategyKeysForEntry($entry);
+            $entryFingerprint = $this->entryFingerprint($entry);
+            $entryMatches[$entryFingerprint] = $matchingKeys;
+
+            if ($matchingKeys === []) {
+                $rejectedScopeEntries[] = $entry;
+
+                continue;
+            }
+
+            $matchedScopeEntries[] = $entry;
+            $matchedStrategyKeys = array_values(array_unique(array_merge($matchedStrategyKeys, $matchingKeys)));
+        }
+
+        sort($matchedStrategyKeys, SORT_STRING);
+
+        if ($rejectedScopeEntries !== []) {
+            return CompareStrategySelection::unsupported(
+                matchedScopeEntries: $matchedScopeEntries,
+                rejectedScopeEntries: $rejectedScopeEntries,
+                diagnostics: [
+                    'matched_strategy_keys' => $matchedStrategyKeys,
+                    'entry_matches' => $entryMatches,
+                ],
+            );
+        }
+
+        if (count($matchedStrategyKeys) !== 1) {
+            return CompareStrategySelection::mixed(
+                matchedScopeEntries: $matchedScopeEntries,
+                diagnostics: [
+                    'matched_strategy_keys' => $matchedStrategyKeys,
+                    'entry_matches' => $entryMatches,
+                ],
+            );
+        }
+
+        return CompareStrategySelection::supported(
+            strategyKey: $matchedStrategyKeys[0],
+            matchedScopeEntries: $matchedScopeEntries,
+            diagnostics: [
+                'matched_strategy_keys' => $matchedStrategyKeys,
+                'entry_matches' => $entryMatches,
+            ],
+        );
+    }
+
+    /**
+     * @param  array{domain_key?: mixed, subject_class?: mixed, subject_type_keys?: mixed, filters?: mixed}  $entry
+     * @return list<string>
+     */
+    private function matchingStrategyKeysForEntry(array $entry): array
+    {
+        $matches = [];
+
+        foreach ($this->all() as $strategy) {
+            foreach ($strategy->capabilities() as $capability) {
+                if (! $capability->supportsEntry($entry)) {
+                    continue;
+                }
+
+                $matches[] = $strategy->key()->value;
+
+                break;
+            }
+        }
+
+        $matches = array_values(array_unique($matches));
+        sort($matches, SORT_STRING);
+
+        return $matches;
+    }
+
+    /**
+     * @return list<array{domain_key: string, subject_class: string, subject_type_keys: list<string>, filters: array<string, mixed>}>
+     */
+    private function entriesForScope(BaselineScope $scope): array
+    {
+        if ($scope->entries !== []) {
+            return $scope->entries;
+        }
+
+        $entries = [];
+
+        if ($scope->policyTypes !== []) {
+            $entries[] = [
+                'domain_key' => GovernanceDomainKey::Intune->value,
+                'subject_class' => GovernanceSubjectClass::Policy->value,
+                'subject_type_keys' => $scope->policyTypes,
+                'filters' => [],
+            ];
+        }
+
+        if ($scope->foundationTypes !== []) {
+            $entries[] = [
+                'domain_key' => GovernanceDomainKey::PlatformFoundation->value,
+                'subject_class' => GovernanceSubjectClass::ConfigurationResource->value,
+                'subject_type_keys' => $scope->foundationTypes,
+                'filters' => [],
+            ];
+        }
+
+        return $entries;
+    }
+
+    /**
+     * @param  array{domain_key?: mixed, subject_class?: mixed, subject_type_keys?: mixed, filters?: mixed}  $entry
+     */
+    private function entryFingerprint(array $entry): string
+    {
+        $subjectTypeKeys = is_array($entry['subject_type_keys'] ?? null)
+            ? array_values(array_filter($entry['subject_type_keys'], 'is_string'))
+            : [];
+
+        sort($subjectTypeKeys, SORT_STRING);
+
+        return implode('|', [
+            trim((string) ($entry['domain_key'] ?? '')),
+            trim((string) ($entry['subject_class'] ?? '')),
+            implode(',', $subjectTypeKeys),
+        ]);
+    }
+}

apps/platform/app/Support/Baselines/Compare/CompareStrategySelection.php

@@ -0,0 +1,129 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Support\Baselines\Compare;
+
+use InvalidArgumentException;
+
+final class CompareStrategySelection
+{
+    /**
+     * @param  list<array<string, mixed>>  $matchedScopeEntries
+     * @param  list<array<string, mixed>>  $rejectedScopeEntries
+     * @param  array<string, mixed>  $diagnostics
+     */
+    public function __construct(
+        public readonly StrategySelectionState $selectionState,
+        public readonly ?CompareStrategyKey $strategyKey,
+        public readonly array $matchedScopeEntries,
+        public readonly array $rejectedScopeEntries,
+        public readonly string $operatorReason,
+        public readonly array $diagnostics = [],
+    ) {
+        if ($this->selectionState === StrategySelectionState::Supported && ! $this->strategyKey instanceof CompareStrategyKey) {
+            throw new InvalidArgumentException('Supported compare strategy selections require a strategy key.');
+        }
+
+        if (trim($this->operatorReason) === '') {
+            throw new InvalidArgumentException('Compare strategy selections require an operator-safe reason.');
+        }
+    }
+
+    /**
+     * @param  list<array<string, mixed>>  $matchedScopeEntries
+     * @param  array<string, mixed>  $diagnostics
+     */
+    public static function supported(
+        CompareStrategyKey|string $strategyKey,
+        array $matchedScopeEntries,
+        array $diagnostics = [],
+        string $operatorReason = 'Compare strategy resolved successfully.',
+    ): self {
+        return new self(
+            selectionState: StrategySelectionState::Supported,
+            strategyKey: CompareStrategyKey::from($strategyKey),
+            matchedScopeEntries: $matchedScopeEntries,
+            rejectedScopeEntries: [],
+            operatorReason: $operatorReason,
+            diagnostics: $diagnostics,
+        );
+    }
+
+    /**
+     * @param  list<array<string, mixed>>  $matchedScopeEntries
+     * @param  list<array<string, mixed>>  $rejectedScopeEntries
+     * @param  array<string, mixed>  $diagnostics
+     */
+    public static function unsupported(
+        array $matchedScopeEntries,
+        array $rejectedScopeEntries,
+        array $diagnostics = [],
+        string $operatorReason = 'No compare strategy supports the selected governed subjects.',
+    ): self {
+        return new self(
+            selectionState: StrategySelectionState::Unsupported,
+            strategyKey: null,
+            matchedScopeEntries: $matchedScopeEntries,
+            rejectedScopeEntries: $rejectedScopeEntries,
+            operatorReason: $operatorReason,
+            diagnostics: $diagnostics,
+        );
+    }
+
+    /**
+     * @param  list<array<string, mixed>>  $matchedScopeEntries
+     * @param  array<string, mixed>  $diagnostics
+     */
+    public static function mixed(
+        array $matchedScopeEntries,
+        array $diagnostics = [],
+        string $operatorReason = 'The selected governed subjects span multiple compare strategy families.',
+    ): self {
+        return new self(
+            selectionState: StrategySelectionState::Mixed,
+            strategyKey: null,
+            matchedScopeEntries: $matchedScopeEntries,
+            rejectedScopeEntries: [],
+            operatorReason: $operatorReason,
+            diagnostics: $diagnostics,
+        );
+    }
+
+    public function isSupported(): bool
+    {
+        return $this->selectionState === StrategySelectionState::Supported;
+    }
+
+    public function isUnsupported(): bool
+    {
+        return $this->selectionState === StrategySelectionState::Unsupported;
+    }
+
+    public function isMixed(): bool
+    {
+        return $this->selectionState === StrategySelectionState::Mixed;
+    }
+
+    /**
+     * @return array{
+     *   selection_state: string,
+     *   strategy_key: ?string,
+     *   matched_scope_entries: list<array<string, mixed>>,
+     *   rejected_scope_entries: list<array<string, mixed>>,
+     *   operator_reason: string,
+     *   diagnostics: array<string, mixed>
+     * }
+     */
+    public function toArray(): array
+    {
+        return [
+            'selection_state' => $this->selectionState->value,
+            'strategy_key' => $this->strategyKey?->value,
+            'matched_scope_entries' => $this->matchedScopeEntries,
+            'rejected_scope_entries' => $this->rejectedScopeEntries,
+            'operator_reason' => $this->operatorReason,
+            'diagnostics' => $this->diagnostics,
+        ];
+    }
+}

apps/platform/app/Support/Baselines/Compare/CompareSubjectIdentity.php

@@ -0,0 +1,42 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Support\Baselines\Compare;
+
+use InvalidArgumentException;
+
+final class CompareSubjectIdentity
+{
+    public function __construct(
+        public readonly string $domainKey,
+        public readonly string $subjectClass,
+        public readonly string $subjectTypeKey,
+        public readonly ?string $externalSubjectId,
+        public readonly string $subjectKey,
+    ) {
+        if (trim($this->domainKey) === '' || trim($this->subjectClass) === '' || trim($this->subjectTypeKey) === '' || trim($this->subjectKey) === '') {
+            throw new InvalidArgumentException('Compare subject identities require non-empty domain, subject class, subject type key, and subject key values.');
+        }
+    }
+
+    /**
+     * @return array{
+     *   domain_key: string,
+     *   subject_class: string,
+     *   subject_type_key: string,
+     *   external_subject_id: ?string,
+     *   subject_key: string
+     * }
+     */
+    public function toArray(): array
+    {
+        return [
+            'domain_key' => $this->domainKey,
+            'subject_class' => $this->subjectClass,
+            'subject_type_key' => $this->subjectTypeKey,
+            'external_subject_id' => $this->externalSubjectId,
+            'subject_key' => $this->subjectKey,
+        ];
+    }
+}

apps/platform/app/Support/Baselines/Compare/CompareSubjectProjection.php

@@ -0,0 +1,52 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Support\Baselines\Compare;
+
+use InvalidArgumentException;
+
+final class CompareSubjectProjection
+{
+    /**
+     * @param  array<string, string>  $additionalLabels
+     * @param  array<string, mixed>|null  $subjectDescriptor
+     */
+    public function __construct(
+        public readonly string $platformSubjectClass,
+        public readonly string $domainKey,
+        public readonly string $subjectTypeKey,
+        public readonly string $operatorLabel,
+        public readonly ?string $summaryKind = null,
+        public readonly array $additionalLabels = [],
+        public readonly ?array $subjectDescriptor = null,
+    ) {
+        if (trim($this->platformSubjectClass) === '' || trim($this->domainKey) === '' || trim($this->subjectTypeKey) === '' || trim($this->operatorLabel) === '') {
+            throw new InvalidArgumentException('Compare subject projections require non-empty platform subject class, domain key, subject type key, and operator label values.');
+        }
+    }
+
+    /**
+     * @return array{
+     *   platform_subject_class: string,
+     *   domain_key: string,
+     *   subject_type_key: string,
+     *   operator_label: string,
+     *   summary_kind: ?string,
+    *   additional_labels: array<string, string>,
+    *   subject_descriptor: ?array<string, mixed>
+     * }
+     */
+    public function toArray(): array
+    {
+        return [
+            'platform_subject_class' => $this->platformSubjectClass,
+            'domain_key' => $this->domainKey,
+            'subject_type_key' => $this->subjectTypeKey,
+            'operator_label' => $this->operatorLabel,
+            'summary_kind' => $this->summaryKind,
+            'additional_labels' => $this->additionalLabels,
+            'subject_descriptor' => $this->subjectDescriptor,
+        ];
+    }
+}

apps/platform/app/Support/Baselines/Compare/CompareSubjectResult.php

@@ -0,0 +1,119 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Support\Baselines\Compare;
+
+use InvalidArgumentException;
+
+final class CompareSubjectResult
+{
+    /**
+     * @param  array<string, mixed>  $diagnostics
+     */
+    public function __construct(
+        public readonly CompareSubjectIdentity $subjectIdentity,
+        public readonly CompareSubjectProjection $projection,
+        public readonly string $baselineAvailability,
+        public readonly string $currentStateAvailability,
+        public readonly CompareState $compareState,
+        public readonly string $trustLevel,
+        public readonly string $evidenceQuality,
+        public readonly ?string $severityRecommendation = null,
+        public readonly ?CompareFindingCandidate $findingCandidate = null,
+        public readonly array $diagnostics = [],
+    ) {
+        if (trim($this->baselineAvailability) === '' || trim($this->currentStateAvailability) === '' || trim($this->trustLevel) === '' || trim($this->evidenceQuality) === '') {
+            throw new InvalidArgumentException('Compare subject results require non-empty availability, trust level, and evidence quality values.');
+        }
+
+        if ($this->compareState === CompareState::Drift && ! $this->findingCandidate instanceof CompareFindingCandidate) {
+            throw new InvalidArgumentException('Drift compare subject results require a finding candidate.');
+        }
+
+        if ($this->compareState !== CompareState::Drift && $this->findingCandidate instanceof CompareFindingCandidate) {
+            throw new InvalidArgumentException('Only drift compare subject results may carry a finding candidate.');
+        }
+    }
+
+    public function hasFindingCandidate(): bool
+    {
+        return $this->findingCandidate instanceof CompareFindingCandidate;
+    }
+
+    public function isGapState(): bool
+    {
+        return in_array($this->compareState, [
+            CompareState::Unsupported,
+            CompareState::Incomplete,
+            CompareState::Ambiguous,
+            CompareState::Failed,
+        ], true);
+    }
+
+    public function gapReasonCode(): ?string
+    {
+        $reasonCode = $this->diagnostics['reason_code'] ?? null;
+
+        return is_string($reasonCode) && trim($reasonCode) !== '' ? trim($reasonCode) : null;
+    }
+
+    /**
+     * @return array<string, mixed>|null
+     */
+    public function gapRecord(): ?array
+    {
+        $gapRecord = $this->diagnostics['gap_record'] ?? null;
+
+        return is_array($gapRecord) ? $gapRecord : null;
+    }
+
+    /**
+     * @return array{
+     *   subject_identity: array{
+     *     domain_key: string,
+     *     subject_class: string,
+     *     subject_type_key: string,
+     *     external_subject_id: ?string,
+     *     subject_key: string
+     *   },
+     *   projection: array{
+     *     platform_subject_class: string,
+     *     domain_key: string,
+     *     subject_type_key: string,
+     *     operator_label: string,
+     *     summary_kind: ?string,
+     *     additional_labels: array<string, string>
+     *   },
+     *   baseline_availability: string,
+     *   current_state_availability: string,
+     *   compare_state: string,
+     *   trust_level: string,
+     *   evidence_quality: string,
+     *   severity_recommendation: ?string,
+     *   finding_candidate: ?array{
+     *     change_type: string,
+     *     severity: string,
+     *     fingerprint_basis: array<string, mixed>,
+     *     evidence_payload: array<string, mixed>,
+     *     auto_close_eligible: bool
+     *   },
+     *   diagnostics: array<string, mixed>
+     * }
+     */
+    public function toArray(): array
+    {
+        return [
+            'subject_identity' => $this->subjectIdentity->toArray(),
+            'projection' => $this->projection->toArray(),
+            'baseline_availability' => $this->baselineAvailability,
+            'current_state_availability' => $this->currentStateAvailability,
+            'compare_state' => $this->compareState->value,
+            'trust_level' => $this->trustLevel,
+            'evidence_quality' => $this->evidenceQuality,
+            'severity_recommendation' => $this->severityRecommendation,
+            'finding_candidate' => $this->findingCandidate?->toArray(),
+            'diagnostics' => $this->diagnostics,
+        ];
+    }
+}

apps/platform/app/Support/Baselines/Compare/StrategySelectionState.php

@@ -0,0 +1,12 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Support\Baselines\Compare;
+
+enum StrategySelectionState: string
+{
+    case Supported = 'supported';
+    case Unsupported = 'unsupported';
+    case Mixed = 'mixed';
+}

apps/platform/app/Support/CanonicalOperationType.php

@@ -0,0 +1,39 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Support;
+
+final readonly class CanonicalOperationType
+{
+    public function __construct(
+        public string $canonicalCode,
+        public ?string $domainKey,
+        public ?string $artifactFamily,
+        public string $displayLabel,
+        public bool $supportsOperatorExplanation = false,
+        public ?int $expectedDurationSeconds = null,
+    ) {}
+
+    /**
+     * @return array{
+     *     canonical_code: string,
+     *     domain_key: ?string,
+     *     artifact_family: ?string,
+     *     display_label: string,
+     *     supports_operator_explanation: bool,
+     *     expected_duration_seconds: ?int
+     * }
+     */
+    public function toArray(): array
+    {
+        return [
+            'canonical_code' => $this->canonicalCode,
+            'domain_key' => $this->domainKey,
+            'artifact_family' => $this->artifactFamily,
+            'display_label' => $this->displayLabel,
+            'supports_operator_explanation' => $this->supportsOperatorExplanation,
+            'expected_duration_seconds' => $this->expectedDurationSeconds,
+        ];
+    }
+}

apps/platform/app/Support/Filament/FilterOptionCatalog.php

@@ -203,17 +203,7 @@ public static function findingGovernanceAttentionStates(): array
      */
     public static function operationTypes(?iterable $types = null): array
     {
-        $values = collect($types ?? array_keys(OperationCatalog::labels()))
-            ->filter(fn (mixed $type): bool => is_string($type) && trim($type) !== '')
-            ->map(fn (string $type): string => trim($type))
-            ->unique()
-            ->sort()
-            ->values();
-
-        return $values
-            ->mapWithKeys(fn (string $type): array => [$type => OperationCatalog::label($type)])
-            ->sort()
-            ->all();
+        return OperationCatalog::filterOptions($types);
     }
 
     /**

apps/platform/app/Support/Governance/GovernanceSubjectTaxonomyRegistry.php

@@ -76,6 +76,50 @@ public function find(string $domainKey, string $subjectTypeKey): ?GovernanceSubj
         return null;
     }
 
+    public function findBySubjectTypeKey(string $subjectTypeKey, ?string $legacyBucket = null): ?GovernanceSubjectType
+    {
+        $subjectTypeKey = trim($subjectTypeKey);
+        $legacyBucket = is_string($legacyBucket) ? trim($legacyBucket) : null;
+
+        foreach ($this->all() as $subjectType) {
+            if ($subjectType->subjectTypeKey !== $subjectTypeKey) {
+                continue;
+            }
+
+            if ($legacyBucket !== null && $subjectType->legacyBucket !== $legacyBucket) {
+                continue;
+            }
+
+            return $subjectType;
+        }
+
+        return null;
+    }
+
+    /**
+     * @return list<string>
+     */
+    public function canonicalNouns(): array
+    {
+        return ['domain_key', 'subject_class', 'subject_type_key', 'subject_type_label'];
+    }
+
+    public function ownershipDescriptor(?PlatformVocabularyGlossary $glossary = null): RegistryOwnershipDescriptor
+    {
+        $glossary ??= app(PlatformVocabularyGlossary::class);
+
+        return $glossary->registry('governance_subject_taxonomy_registry')
+            ?? RegistryOwnershipDescriptor::fromArray([
+                'registry_key' => 'governance_subject_taxonomy_registry',
+                'boundary_classification' => PlatformVocabularyGlossary::BOUNDARY_CROSS_DOMAIN_GOVERNANCE,
+                'owner_layer' => PlatformVocabularyGlossary::OWNER_PLATFORM_CORE,
+                'source_class_or_file' => self::class,
+                'canonical_nouns' => $this->canonicalNouns(),
+                'allowed_consumers' => ['baseline_scope', 'compare', 'snapshot', 'review'],
+                'compatibility_notes' => 'Governed-subject registry lookups remain the canonical bridge from legacy policy-type payloads to platform-safe descriptors.',
+            ]);
+    }
+
     public function isKnownDomain(string $domainKey): bool
     {
         return array_key_exists(trim($domainKey), self::DOMAIN_CLASSES);

apps/platform/app/Support/Governance/PlatformSubjectDescriptor.php

@@ -0,0 +1,60 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Support\Governance;
+
+use InvalidArgumentException;
+
+final readonly class PlatformSubjectDescriptor
+{
+    public function __construct(
+        public string $domainKey,
+        public string $subjectClass,
+        public string $subjectTypeKey,
+        public string $subjectTypeLabel,
+        public string $platformNoun,
+        public string $displayLabel,
+        public ?string $legacyPolicyType = null,
+        public string $ownerLayer = PlatformVocabularyGlossary::OWNER_PLATFORM_CORE,
+    ) {
+        foreach ([
+            'domain key' => $this->domainKey,
+            'subject class' => $this->subjectClass,
+            'subject type key' => $this->subjectTypeKey,
+            'subject type label' => $this->subjectTypeLabel,
+            'platform noun' => $this->platformNoun,
+            'display label' => $this->displayLabel,
+        ] as $label => $value) {
+            if (trim($value) === '') {
+                throw new InvalidArgumentException(sprintf('Platform subject descriptors require a non-empty %s.', $label));
+            }
+        }
+    }
+
+    /**
+     * @return array{
+     *     domain_key: string,
+     *     subject_class: string,
+     *     subject_type_key: string,
+     *     subject_type_label: string,
+     *     platform_noun: string,
+     *     display_label: string,
+     *     legacy_policy_type: ?string,
+     *     owner_layer: string
+     * }
+     */
+    public function toArray(): array
+    {
+        return [
+            'domain_key' => $this->domainKey,
+            'subject_class' => $this->subjectClass,
+            'subject_type_key' => $this->subjectTypeKey,
+            'subject_type_label' => $this->subjectTypeLabel,
+            'platform_noun' => $this->platformNoun,
+            'display_label' => $this->displayLabel,
+            'legacy_policy_type' => $this->legacyPolicyType,
+            'owner_layer' => $this->ownerLayer,
+        ];
+    }
+}

apps/platform/app/Support/Governance/PlatformSubjectDescriptorNormalizer.php

@@ -0,0 +1,184 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Support\Governance;
+
+use Illuminate\Support\Str;
+
+final class PlatformSubjectDescriptorNormalizer
+{
+    public function __construct(
+        private readonly GovernanceSubjectTaxonomyRegistry $registry,
+        private readonly PlatformVocabularyGlossary $glossary,
+    ) {}
+
+    /**
+     * @param  array<string, mixed>  $payload
+     */
+    public function fromArray(array $payload, string $sourceSurface = 'runtime'): SubjectDescriptorNormalizationResult
+    {
+        $usedLegacySource = ! isset($payload['subject_type_key'])
+            && (isset($payload['policy_type']) || isset($payload['subject_type']));
+
+        $subjectTypeKey = $this->stringValue(
+            $payload['subject_type_key']
+            ?? $payload['policy_type']
+            ?? $payload['subject_type']
+            ?? null,
+        );
+
+        $result = $this->normalize(
+            subjectTypeKey: $subjectTypeKey,
+            domainKey: $this->stringValue($payload['domain_key'] ?? null),
+            subjectClass: $this->stringValue($payload['subject_class'] ?? null),
+            legacyPolicyType: $this->stringValue($payload['policy_type'] ?? null),
+            sourceSurface: $sourceSurface,
+        );
+
+        if (! $usedLegacySource || $result->usedLegacyAlias) {
+            return $result;
+        }
+
+        return new SubjectDescriptorNormalizationResult(
+            descriptor: $result->descriptor,
+            sourceSurface: $result->sourceSurface,
+            usedLegacyAlias: true,
+            warnings: array_values(array_unique(array_merge(
+                ['Resolved a compatibility-only policy_type payload through governed-subject normalization.'],
+                $result->warnings,
+            ))),
+        );
+    }
+
+    public function fromLegacyBucket(string $legacyBucket, string $subjectTypeKey, string $sourceSurface = 'runtime'): SubjectDescriptorNormalizationResult
+    {
+        $subjectType = $this->registry->findBySubjectTypeKey($subjectTypeKey, $legacyBucket);
+
+        return $this->buildResult(
+            subjectType: $subjectType,
+            sourceSurface: $sourceSurface,
+            legacyPolicyType: $subjectTypeKey,
+            usedLegacyAlias: true,
+        );
+    }
+
+    public function normalize(
+        ?string $subjectTypeKey,
+        ?string $domainKey = null,
+        ?string $subjectClass = null,
+        ?string $legacyPolicyType = null,
+        string $sourceSurface = 'runtime',
+    ): SubjectDescriptorNormalizationResult {
+        $subjectType = null;
+
+        if (is_string($subjectTypeKey) && trim($subjectTypeKey) !== '') {
+            $subjectType = $domainKey !== null
+                ? $this->registry->find($domainKey, $subjectTypeKey)
+                : $this->registry->findBySubjectTypeKey($subjectTypeKey);
+        }
+
+        if ($subjectType === null && is_string($legacyPolicyType) && trim($legacyPolicyType) !== '') {
+            return $this->fromLegacyBucket('policy_types', $legacyPolicyType, $sourceSurface);
+        }
+
+        return $this->buildResult(
+            subjectType: $subjectType,
+            sourceSurface: $sourceSurface,
+            explicitDomainKey: $domainKey,
+            explicitSubjectClass: $subjectClass,
+            legacyPolicyType: $legacyPolicyType,
+            usedLegacyAlias: false,
+        );
+    }
+
+    /**
+     * @param  list<array{domain_key: string, subject_class: string, subject_type_keys: list<string>, filters: array<string, mixed>}>  $entries
+     * @return list<array<string, mixed>>
+     */
+    public function descriptorsForScopeEntries(array $entries): array
+    {
+        $descriptors = [];
+
+        foreach ($entries as $entry) {
+            foreach ($entry['subject_type_keys'] as $subjectTypeKey) {
+                $result = $this->normalize(
+                    subjectTypeKey: $subjectTypeKey,
+                    domainKey: $entry['domain_key'],
+                    subjectClass: $entry['subject_class'],
+                    legacyPolicyType: $subjectTypeKey,
+                    sourceSurface: 'baseline_scope',
+                );
+
+                $descriptors[] = $result->toArray();
+            }
+        }
+
+        return $descriptors;
+    }
+
+    private function buildResult(
+        ?GovernanceSubjectType $subjectType,
+        string $sourceSurface,
+        ?string $explicitDomainKey = null,
+        ?string $explicitSubjectClass = null,
+        ?string $legacyPolicyType = null,
+        bool $usedLegacyAlias = false,
+    ): SubjectDescriptorNormalizationResult {
+        $platformNoun = $this->glossary->term('governed_subject')?->canonicalLabel ?? 'Governed subject';
+        $warnings = [];
+
+        if (! $subjectType instanceof GovernanceSubjectType) {
+            $warnings[] = 'Governed-subject descriptor fell back to compatibility-only naming because the subject type could not be resolved in the taxonomy registry.';
+
+            return new SubjectDescriptorNormalizationResult(
+                descriptor: new PlatformSubjectDescriptor(
+                    domainKey: $explicitDomainKey ?? GovernanceDomainKey::Intune->value,
+                    subjectClass: $explicitSubjectClass ?? GovernanceSubjectClass::Policy->value,
+                    subjectTypeKey: $legacyPolicyType ?? 'unknown_subject',
+                    subjectTypeLabel: Str::headline($legacyPolicyType ?? 'Unknown subject'),
+                    platformNoun: $platformNoun,
+                    displayLabel: Str::headline($legacyPolicyType ?? 'Unknown subject'),
+                    legacyPolicyType: $legacyPolicyType,
+                ),
+                sourceSurface: $sourceSurface,
+                usedLegacyAlias: true,
+                warnings: $warnings,
+            );
+        }
+
+        if ($usedLegacyAlias) {
+            $warnings[] = sprintf(
+                'Resolved legacy subject alias "%s" through the governed-subject taxonomy registry for %s.',
+                $legacyPolicyType ?? $subjectType->subjectTypeKey,
+                $sourceSurface,
+            );
+        }
+
+        return new SubjectDescriptorNormalizationResult(
+            descriptor: new PlatformSubjectDescriptor(
+                domainKey: $subjectType->domainKey->value,
+                subjectClass: $subjectType->subjectClass->value,
+                subjectTypeKey: $subjectType->subjectTypeKey,
+                subjectTypeLabel: $subjectType->label,
+                platformNoun: $platformNoun,
+                displayLabel: $subjectType->label,
+                legacyPolicyType: $legacyPolicyType,
+            ),
+            sourceSurface: $sourceSurface,
+            usedLegacyAlias: $usedLegacyAlias,
+            warnings: $warnings,
+        );
+    }
+
+    private function stringValue(mixed $value): ?string
+    {
+        if (! is_string($value)) {
+            return null;
+        }
+
+        $trimmed = trim($value);
+
+        return $trimmed !== '' ? $trimmed : null;
+    }
+}

apps/platform/app/Support/Governance/PlatformVocabularyGlossary.php

@@ -0,0 +1,570 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Support\Governance;
+
+use App\Support\Inventory\InventoryPolicyTypeMeta;
+use App\Support\OperationCatalog;
+use App\Support\Providers\ProviderReasonCodes;
+
+final class PlatformVocabularyGlossary
+{
+    public const string BOUNDARY_PLATFORM_CORE = 'platform_core';
+
+    public const string BOUNDARY_CROSS_DOMAIN_GOVERNANCE = 'cross_domain_governance';
+
+    public const string BOUNDARY_INTUNE_SPECIFIC = 'intune_specific';
+
+    public const string OWNER_PLATFORM_CORE = 'platform_core';
+
+    public const string OWNER_DOMAIN_OWNED = 'domain_owned';
+
+    public const string OWNER_PROVIDER_OWNED = 'provider_owned';
+
+    public const string OWNER_COMPATIBILITY_ALIAS = 'compatibility_alias';
+
+    public const string OWNER_COMPATIBILITY_ONLY = 'compatibility_only';
+
+    /**
+     * @return list<PlatformVocabularyTerm>
+     */
+    public function terms(): array
+    {
+        return array_values(array_map(
+            static fn (array $term): PlatformVocabularyTerm => PlatformVocabularyTerm::fromArray($term),
+            $this->configuredTerms(),
+        ));
+    }
+
+    public function term(string $term): ?PlatformVocabularyTerm
+    {
+        $normalized = trim(mb_strtolower($term));
+
+        foreach ($this->terms() as $candidate) {
+            if (trim(mb_strtolower($candidate->termKey)) === $normalized) {
+                return $candidate;
+            }
+        }
+
+        return $this->resolveAlias($term);
+    }
+
+    public function resolveAlias(string $term, ?string $context = null): ?PlatformVocabularyTerm
+    {
+        $normalized = trim(mb_strtolower($term));
+        $normalizedContext = is_string($context) ? trim(mb_strtolower($context)) : null;
+
+        foreach ($this->terms() as $candidate) {
+            $aliases = array_map(
+                static fn (string $alias): string => trim(mb_strtolower($alias)),
+                $candidate->legacyAliases,
+            );
+
+            if (! in_array($normalized, $aliases, true)) {
+                continue;
+            }
+
+            if ($normalizedContext !== null && $candidate->allowedContexts !== []) {
+                $contexts = array_map(
+                    static fn (string $allowedContext): string => trim(mb_strtolower($allowedContext)),
+                    $candidate->allowedContexts,
+                );
+
+                if (! in_array($normalizedContext, $contexts, true)) {
+                    continue;
+                }
+            }
+
+            return $candidate;
+        }
+
+        return null;
+    }
+
+    public function canonicalName(string $term): ?string
+    {
+        return $this->term($term)?->termKey;
+    }
+
+    public function isCanonical(string $term): bool
+    {
+        $resolved = $this->term($term);
+
+        if (! $resolved instanceof PlatformVocabularyTerm) {
+            return false;
+        }
+
+        return trim(mb_strtolower($term)) === trim(mb_strtolower($resolved->termKey));
+    }
+
+    public function ownership(string $term): ?string
+    {
+        return $this->term($term)?->ownerLayer;
+    }
+
+    /**
+     * @return list<string>
+     */
+    public function canonicalTerms(): array
+    {
+        return array_values(array_map(
+            static fn (PlatformVocabularyTerm $term): string => $term->termKey,
+            $this->terms(),
+        ));
+    }
+
+    /**
+     * @return array<string, array{
+     *     term_key: string,
+     *     canonical_label: string,
+     *     canonical_description: string,
+     *     boundary_classification: string,
+     *     owner_layer: string,
+     *     allowed_contexts: list<string>,
+     *     legacy_aliases: list<string>,
+     *     alias_retirement_path: ?string,
+     *     forbidden_platform_aliases: list<string>
+     * }>
+     */
+    public function termInventory(): array
+    {
+        return collect($this->terms())
+            ->mapWithKeys(static fn (PlatformVocabularyTerm $term): array => [
+                $term->termKey => $term->toArray(),
+            ])
+            ->all();
+    }
+
+    /**
+     * @return array<string, list<string>>
+     */
+    public function legacyAliases(): array
+    {
+        return collect($this->terms())
+            ->filter(static fn (PlatformVocabularyTerm $term): bool => $term->legacyAliases !== [])
+            ->mapWithKeys(static fn (PlatformVocabularyTerm $term): array => [
+                $term->termKey => $term->legacyAliases,
+            ])
+            ->all();
+    }
+
+    /**
+     * @return array<string, array{
+     *     canonical_name: string,
+     *     legacy_aliases: list<string>,
+     *     retirement_path: ?string,
+     *     forbidden_platform_aliases: list<string>
+     * }>
+     */
+    public function aliasRetirementInventory(): array
+    {
+        return collect($this->terms())
+            ->filter(static fn (PlatformVocabularyTerm $term): bool => $term->legacyAliases !== [])
+            ->mapWithKeys(static fn (PlatformVocabularyTerm $term): array => [
+                $term->termKey => [
+                    'canonical_name' => $term->termKey,
+                    'legacy_aliases' => $term->legacyAliases,
+                    'retirement_path' => $term->aliasRetirementPath,
+                    'forbidden_platform_aliases' => $term->forbiddenPlatformAliases,
+                ],
+            ])
+            ->all();
+    }
+
+    public function boundaryClassification(string $term): ?string
+    {
+        return $this->term($term)?->boundaryClassification;
+    }
+
+    /**
+     * @return list<string>
+     */
+    public function allowedBoundaryClassifications(): array
+    {
+        return [
+            self::BOUNDARY_PLATFORM_CORE,
+            self::BOUNDARY_CROSS_DOMAIN_GOVERNANCE,
+            self::BOUNDARY_INTUNE_SPECIFIC,
+        ];
+    }
+
+    /**
+     * @return list<RegistryOwnershipDescriptor>
+     */
+    public function registries(): array
+    {
+        return array_values(array_map(
+            static fn (array $descriptor): RegistryOwnershipDescriptor => RegistryOwnershipDescriptor::fromArray($descriptor),
+            $this->configuredRegistries(),
+        ));
+    }
+
+    public function registry(string $registryKey): ?RegistryOwnershipDescriptor
+    {
+        $normalized = trim(mb_strtolower($registryKey));
+
+        foreach ($this->registries() as $descriptor) {
+            if (trim(mb_strtolower($descriptor->registryKey)) === $normalized) {
+                return $descriptor;
+            }
+        }
+
+        return null;
+    }
+
+    /**
+     * @return array<string, array{
+     *     registry_key: string,
+     *     boundary_classification: string,
+     *     owner_layer: string,
+     *     source_class_or_file: string,
+     *     canonical_nouns: list<string>,
+     *     allowed_consumers: list<string>,
+     *     compatibility_notes: ?string
+     * }>
+     */
+    public function registryInventory(): array
+    {
+        return collect($this->registries())
+            ->mapWithKeys(static fn (RegistryOwnershipDescriptor $descriptor): array => [
+                $descriptor->registryKey => $descriptor->toArray(),
+            ])
+            ->all();
+    }
+
+    /**
+     * @return array<string, array{
+     *     owner_namespace: string,
+     *     boundary_classification: string,
+     *     owner_layer: string,
+     *     compatibility_notes: ?string
+     * }>
+     */
+    public function reasonNamespaceInventory(): array
+    {
+        return $this->configuredReasonNamespaces();
+    }
+
+    /**
+     * @return array{
+     *     owner_namespace: string,
+     *     boundary_classification: string,
+     *     owner_layer: string,
+     *     compatibility_notes: ?string
+     * }|null
+     */
+    public function reasonNamespace(string $ownerNamespace): ?array
+    {
+        $normalized = trim(mb_strtolower($ownerNamespace));
+
+        foreach ($this->reasonNamespaceInventory() as $descriptor) {
+            $candidate = is_string($descriptor['owner_namespace'] ?? null)
+                ? trim(mb_strtolower((string) $descriptor['owner_namespace']))
+                : null;
+
+            if ($candidate === $normalized) {
+                return $descriptor;
+            }
+        }
+
+        return null;
+    }
+
+    public function classifyReasonNamespace(string $ownerNamespace): ?string
+    {
+        return $this->reasonNamespace($ownerNamespace)['boundary_classification'] ?? null;
+    }
+
+    public function classifyOperationType(string $operationType): ?string
+    {
+        if (trim($operationType) === '') {
+            return null;
+        }
+
+        return $this->registry('operation_catalog')?->boundaryClassification;
+    }
+
+    /**
+     * @return array<string, array<string, mixed>>
+     */
+    private function configuredTerms(): array
+    {
+        $configured = config('tenantpilot.platform_vocabulary.terms');
+
+        if (is_array($configured) && $configured !== []) {
+            return $configured;
+        }
+
+        return [
+            'governed_subject' => [
+                'term_key' => 'governed_subject',
+                'canonical_label' => 'Governed subject',
+                'canonical_description' => 'The platform-facing noun for a governed object across compare, snapshot, evidence, and review surfaces.',
+                'boundary_classification' => self::BOUNDARY_PLATFORM_CORE,
+                'owner_layer' => self::OWNER_PLATFORM_CORE,
+                'allowed_contexts' => ['compare', 'snapshot', 'evidence', 'review', 'reporting'],
+                'legacy_aliases' => ['policy_type'],
+                'alias_retirement_path' => 'Retire false-universal policy_type wording from platform-owned summaries and descriptors while preserving Intune-owned storage.',
+                'forbidden_platform_aliases' => ['policy_type'],
+            ],
+            'domain_key' => [
+                'term_key' => 'domain_key',
+                'canonical_label' => 'Governance domain',
+                'canonical_description' => 'The canonical domain discriminator for cross-domain and platform-near contracts.',
+                'boundary_classification' => self::BOUNDARY_CROSS_DOMAIN_GOVERNANCE,
+                'owner_layer' => self::OWNER_PLATFORM_CORE,
+                'allowed_contexts' => ['governance', 'compare', 'snapshot', 'reporting'],
+                'legacy_aliases' => [],
+                'alias_retirement_path' => null,
+                'forbidden_platform_aliases' => [],
+            ],
+            'subject_class' => [
+                'term_key' => 'subject_class',
+                'canonical_label' => 'Subject class',
+                'canonical_description' => 'The canonical subject-class discriminator for governed-subject contracts.',
+                'boundary_classification' => self::BOUNDARY_CROSS_DOMAIN_GOVERNANCE,
+                'owner_layer' => self::OWNER_PLATFORM_CORE,
+                'allowed_contexts' => ['governance', 'compare', 'snapshot'],
+                'legacy_aliases' => [],
+                'alias_retirement_path' => null,
+                'forbidden_platform_aliases' => [],
+            ],
+            'subject_type_key' => [
+                'term_key' => 'subject_type_key',
+                'canonical_label' => 'Governed subject key',
+                'canonical_description' => 'The domain-owned subject-family key used by platform-near descriptors.',
+                'boundary_classification' => self::BOUNDARY_CROSS_DOMAIN_GOVERNANCE,
+                'owner_layer' => self::OWNER_PLATFORM_CORE,
+                'allowed_contexts' => ['governance', 'compare', 'snapshot', 'evidence'],
+                'legacy_aliases' => ['policy_type'],
+                'alias_retirement_path' => 'Prefer subject_type_key on platform-near payloads and keep policy_type only where the owning model is Intune-specific.',
+                'forbidden_platform_aliases' => ['policy_type'],
+            ],
+            'subject_type_label' => [
+                'term_key' => 'subject_type_label',
+                'canonical_label' => 'Governed subject label',
+                'canonical_description' => 'The operator-facing label for a governed subject family.',
+                'boundary_classification' => self::BOUNDARY_CROSS_DOMAIN_GOVERNANCE,
+                'owner_layer' => self::OWNER_PLATFORM_CORE,
+                'allowed_contexts' => ['snapshot', 'evidence', 'compare', 'review'],
+                'legacy_aliases' => [],
+                'alias_retirement_path' => null,
+                'forbidden_platform_aliases' => [],
+            ],
+            'resource_type' => [
+                'term_key' => 'resource_type',
+                'canonical_label' => 'Resource type',
+                'canonical_description' => 'Optional resource-shaped noun for platform-facing summaries when a governed subject also needs a resource family label.',
+                'boundary_classification' => self::BOUNDARY_PLATFORM_CORE,
+                'owner_layer' => self::OWNER_PLATFORM_CORE,
+                'allowed_contexts' => ['reporting', 'review'],
+                'legacy_aliases' => [],
+                'alias_retirement_path' => null,
+                'forbidden_platform_aliases' => [],
+            ],
+            'operation_type' => [
+                'term_key' => 'operation_type',
+                'canonical_label' => 'Operation type',
+                'canonical_description' => 'The canonical platform operation identifier shown on monitoring and launch surfaces.',
+                'boundary_classification' => self::BOUNDARY_PLATFORM_CORE,
+                'owner_layer' => self::OWNER_PLATFORM_CORE,
+                'allowed_contexts' => ['monitoring', 'reporting', 'launch_surfaces'],
+                'legacy_aliases' => ['type'],
+                'alias_retirement_path' => 'Expose canonical operation_type on read models while operation_runs.type remains a compatibility storage seam during rollout.',
+                'forbidden_platform_aliases' => [],
+            ],
+            'platform_reason_family' => [
+                'term_key' => 'platform_reason_family',
+                'canonical_label' => 'Platform reason family',
+                'canonical_description' => 'The cross-domain platform family that explains the top-level cause category without erasing domain ownership.',
+                'boundary_classification' => self::BOUNDARY_PLATFORM_CORE,
+                'owner_layer' => self::OWNER_PLATFORM_CORE,
+                'allowed_contexts' => ['reason_translation', 'monitoring', 'review', 'reporting'],
+                'legacy_aliases' => [],
+                'alias_retirement_path' => null,
+                'forbidden_platform_aliases' => [],
+            ],
+            'reason_owner.owner_namespace' => [
+                'term_key' => 'reason_owner.owner_namespace',
+                'canonical_label' => 'Reason owner namespace',
+                'canonical_description' => 'The explicit namespace that marks whether a translated reason is provider-owned, governance-owned, access-owned, or runtime-owned.',
+                'boundary_classification' => self::BOUNDARY_PLATFORM_CORE,
+                'owner_layer' => self::OWNER_PLATFORM_CORE,
+                'allowed_contexts' => ['reason_translation', 'review', 'reporting'],
+                'legacy_aliases' => [],
+                'alias_retirement_path' => null,
+                'forbidden_platform_aliases' => [],
+            ],
+            'reason_code' => [
+                'term_key' => 'reason_code',
+                'canonical_label' => 'Reason code',
+                'canonical_description' => 'The original domain-owned or provider-owned reason identifier preserved for diagnostics and translation lookup.',
+                'boundary_classification' => self::BOUNDARY_PLATFORM_CORE,
+                'owner_layer' => self::OWNER_PLATFORM_CORE,
+                'allowed_contexts' => ['reason_translation', 'diagnostics'],
+                'legacy_aliases' => [],
+                'alias_retirement_path' => null,
+                'forbidden_platform_aliases' => [],
+            ],
+            'registry_key' => [
+                'term_key' => 'registry_key',
+                'canonical_label' => 'Registry key',
+                'canonical_description' => 'The stable identifier for a contributor-facing registry or catalog.',
+                'boundary_classification' => self::BOUNDARY_PLATFORM_CORE,
+                'owner_layer' => self::OWNER_PLATFORM_CORE,
+                'allowed_contexts' => ['governance', 'contributor_guidance'],
+                'legacy_aliases' => [],
+                'alias_retirement_path' => null,
+                'forbidden_platform_aliases' => [],
+            ],
+            'boundary_classification' => [
+                'term_key' => 'boundary_classification',
+                'canonical_label' => 'Boundary classification',
+                'canonical_description' => 'The explicit classification that marks a term or registry as platform_core, cross_domain_governance, or intune_specific.',
+                'boundary_classification' => self::BOUNDARY_PLATFORM_CORE,
+                'owner_layer' => self::OWNER_PLATFORM_CORE,
+                'allowed_contexts' => ['governance', 'contributor_guidance'],
+                'legacy_aliases' => [],
+                'alias_retirement_path' => null,
+                'forbidden_platform_aliases' => [],
+            ],
+            'policy_type' => [
+                'term_key' => 'policy_type',
+                'canonical_label' => 'Intune policy type',
+                'canonical_description' => 'The Intune-specific discriminator that remains valid on adapter-owned or Intune-owned models but must not be treated as a universal platform noun.',
+                'boundary_classification' => self::BOUNDARY_INTUNE_SPECIFIC,
+                'owner_layer' => self::OWNER_DOMAIN_OWNED,
+                'allowed_contexts' => ['intune_adapter', 'intune_inventory', 'intune_backup'],
+                'legacy_aliases' => [],
+                'alias_retirement_path' => null,
+                'forbidden_platform_aliases' => ['governed_subject'],
+            ],
+        ];
+    }
+
+    /**
+     * @return array<string, array<string, mixed>>
+     */
+    private function configuredRegistries(): array
+    {
+        $configured = config('tenantpilot.platform_vocabulary.registries');
+
+        if (is_array($configured) && $configured !== []) {
+            return $configured;
+        }
+
+        return [
+            'governance_subject_taxonomy_registry' => [
+                'registry_key' => 'governance_subject_taxonomy_registry',
+                'boundary_classification' => self::BOUNDARY_CROSS_DOMAIN_GOVERNANCE,
+                'owner_layer' => self::OWNER_PLATFORM_CORE,
+                'source_class_or_file' => GovernanceSubjectTaxonomyRegistry::class,
+                'canonical_nouns' => ['domain_key', 'subject_class', 'subject_type_key', 'subject_type_label'],
+                'allowed_consumers' => ['baseline_scope', 'compare', 'snapshot', 'review'],
+                'compatibility_notes' => 'Provides the governed-subject source of truth, resolves legacy policy-type payloads, and preserves inactive or future-domain entries without exposing them as active operator choices.',
+            ],
+            'operation_catalog' => [
+                'registry_key' => 'operation_catalog',
+                'boundary_classification' => self::BOUNDARY_PLATFORM_CORE,
+                'owner_layer' => self::OWNER_PLATFORM_CORE,
+                'source_class_or_file' => OperationCatalog::class,
+                'canonical_nouns' => ['operation_type'],
+                'allowed_consumers' => ['monitoring', 'reporting', 'launch_surfaces', 'audit'],
+                'compatibility_notes' => 'Resolves canonical operation meaning from historical storage values without treating every stored raw string as equally canonical.',
+            ],
+            'provider_reason_codes' => [
+                'registry_key' => 'provider_reason_codes',
+                'boundary_classification' => self::BOUNDARY_INTUNE_SPECIFIC,
+                'owner_layer' => self::OWNER_PROVIDER_OWNED,
+                'source_class_or_file' => ProviderReasonCodes::class,
+                'canonical_nouns' => ['reason_code'],
+                'allowed_consumers' => ['reason_translation'],
+                'compatibility_notes' => 'Provider-owned reason codes remain namespaced domain details and become platform-safe only through the reason-translation boundary.',
+            ],
+            'inventory_policy_type_catalog' => [
+                'registry_key' => 'inventory_policy_type_catalog',
+                'boundary_classification' => self::BOUNDARY_INTUNE_SPECIFIC,
+                'owner_layer' => self::OWNER_DOMAIN_OWNED,
+                'source_class_or_file' => InventoryPolicyTypeMeta::class,
+                'canonical_nouns' => ['policy_type'],
+                'allowed_consumers' => ['intune_adapter', 'inventory', 'backup'],
+                'compatibility_notes' => 'The supported Intune policy-type list is not a universal platform registry and must be wrapped before reuse on platform-near summaries.',
+            ],
+        ];
+    }
+
+    /**
+     * @return array<string, array{
+     *     owner_namespace: string,
+     *     boundary_classification: string,
+     *     owner_layer: string,
+     *     compatibility_notes: ?string
+     * }>
+     */
+    private function configuredReasonNamespaces(): array
+    {
+        $configured = config('tenantpilot.platform_vocabulary.reason_namespaces');
+
+        if (is_array($configured) && $configured !== []) {
+            return $configured;
+        }
+
+        return [
+            'tenant_operability' => [
+                'owner_namespace' => 'tenant_operability',
+                'boundary_classification' => self::BOUNDARY_PLATFORM_CORE,
+                'owner_layer' => self::OWNER_PLATFORM_CORE,
+                'compatibility_notes' => 'Tenant operability reasons are platform-core guardrails for workspace and tenant context.',
+            ],
+            'execution_denial' => [
+                'owner_namespace' => 'execution_denial',
+                'boundary_classification' => self::BOUNDARY_PLATFORM_CORE,
+                'owner_layer' => self::OWNER_PLATFORM_CORE,
+                'compatibility_notes' => 'Execution denial reasons remain platform-core run-legitimacy semantics.',
+            ],
+            'operation_lifecycle' => [
+                'owner_namespace' => 'operation_lifecycle',
+                'boundary_classification' => self::BOUNDARY_PLATFORM_CORE,
+                'owner_layer' => self::OWNER_PLATFORM_CORE,
+                'compatibility_notes' => 'Lifecycle reconciliation reasons remain platform-core monitoring semantics.',
+            ],
+            'governance.baseline_compare' => [
+                'owner_namespace' => 'governance.baseline_compare',
+                'boundary_classification' => self::BOUNDARY_CROSS_DOMAIN_GOVERNANCE,
+                'owner_layer' => self::OWNER_DOMAIN_OWNED,
+                'compatibility_notes' => 'Baseline-compare reason codes are governance-owned details translated through the platform boundary.',
+            ],
+            'governance.artifact_truth' => [
+                'owner_namespace' => 'governance.artifact_truth',
+                'boundary_classification' => self::BOUNDARY_CROSS_DOMAIN_GOVERNANCE,
+                'owner_layer' => self::OWNER_DOMAIN_OWNED,
+                'compatibility_notes' => 'Artifact-truth reason codes remain governance-owned and are surfaced through platform-safe summaries.',
+            ],
+            'provider.microsoft_graph' => [
+                'owner_namespace' => 'provider.microsoft_graph',
+                'boundary_classification' => self::BOUNDARY_INTUNE_SPECIFIC,
+                'owner_layer' => self::OWNER_PROVIDER_OWNED,
+                'compatibility_notes' => 'Microsoft Graph provider reasons remain provider-owned and Intune-specific.',
+            ],
+            'provider.intune_rbac' => [
+                'owner_namespace' => 'provider.intune_rbac',
+                'boundary_classification' => self::BOUNDARY_INTUNE_SPECIFIC,
+                'owner_layer' => self::OWNER_PROVIDER_OWNED,
+                'compatibility_notes' => 'Provider-owned Intune RBAC reasons remain Intune-specific.',
+            ],
+            'rbac.intune' => [
+                'owner_namespace' => 'rbac.intune',
+                'boundary_classification' => self::BOUNDARY_INTUNE_SPECIFIC,
+                'owner_layer' => self::OWNER_DOMAIN_OWNED,
+                'compatibility_notes' => 'RBAC detail remains Intune-specific domain context.',
+            ],
+            'reason_translation.fallback' => [
+                'owner_namespace' => 'reason_translation.fallback',
+                'boundary_classification' => self::BOUNDARY_PLATFORM_CORE,
+                'owner_layer' => self::OWNER_PLATFORM_CORE,
+                'compatibility_notes' => 'Fallback translation remains a platform-core compatibility seam until a domain owner is known.',
+            ],
+        ];
+    }
+}

apps/platform/app/Support/Governance/PlatformVocabularyTerm.php

@@ -0,0 +1,110 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Support\Governance;
+
+use InvalidArgumentException;
+
+final readonly class PlatformVocabularyTerm
+{
+    /**
+     * @param  list<string>  $allowedContexts
+     * @param  list<string>  $legacyAliases
+     * @param  list<string>  $forbiddenPlatformAliases
+     */
+    public function __construct(
+        public string $termKey,
+        public string $canonicalLabel,
+        public string $canonicalDescription,
+        public string $boundaryClassification,
+        public string $ownerLayer,
+        public array $allowedContexts = [],
+        public array $legacyAliases = [],
+        public ?string $aliasRetirementPath = null,
+        public array $forbiddenPlatformAliases = [],
+    ) {
+        if (trim($this->termKey) === '' || trim($this->canonicalLabel) === '' || trim($this->canonicalDescription) === '') {
+            throw new InvalidArgumentException('Platform vocabulary terms require a key, label, and description.');
+        }
+
+        if ($this->legacyAliases !== [] && blank($this->aliasRetirementPath)) {
+            throw new InvalidArgumentException('Platform vocabulary terms with legacy aliases must declare an alias retirement path.');
+        }
+    }
+
+    /**
+     * @param  array<string, mixed>  $data
+     */
+    public static function fromArray(array $data): self
+    {
+        return new self(
+            termKey: (string) ($data['term_key'] ?? ''),
+            canonicalLabel: (string) ($data['canonical_label'] ?? ''),
+            canonicalDescription: (string) ($data['canonical_description'] ?? ''),
+            boundaryClassification: (string) ($data['boundary_classification'] ?? ''),
+            ownerLayer: (string) ($data['owner_layer'] ?? ''),
+            allowedContexts: self::stringList($data['allowed_contexts'] ?? []),
+            legacyAliases: self::stringList($data['legacy_aliases'] ?? []),
+            aliasRetirementPath: is_string($data['alias_retirement_path'] ?? null)
+                ? trim((string) $data['alias_retirement_path'])
+                : null,
+            forbiddenPlatformAliases: self::stringList($data['forbidden_platform_aliases'] ?? []),
+        );
+    }
+
+    public function matches(string $term): bool
+    {
+        $normalized = trim(mb_strtolower($term));
+
+        if ($normalized === '') {
+            return false;
+        }
+
+        return in_array($normalized, array_map(
+            static fn (string $candidate): string => trim(mb_strtolower($candidate)),
+            array_merge([$this->termKey], $this->legacyAliases),
+        ), true);
+    }
+
+    /**
+     * @return array{
+     *     term_key: string,
+     *     canonical_label: string,
+     *     canonical_description: string,
+     *     boundary_classification: string,
+     *     owner_layer: string,
+     *     allowed_contexts: list<string>,
+     *     legacy_aliases: list<string>,
+     *     alias_retirement_path: ?string,
+     *     forbidden_platform_aliases: list<string>
+     * }
+     */
+    public function toArray(): array
+    {
+        return [
+            'term_key' => $this->termKey,
+            'canonical_label' => $this->canonicalLabel,
+            'canonical_description' => $this->canonicalDescription,
+            'boundary_classification' => $this->boundaryClassification,
+            'owner_layer' => $this->ownerLayer,
+            'allowed_contexts' => $this->allowedContexts,
+            'legacy_aliases' => $this->legacyAliases,
+            'alias_retirement_path' => $this->aliasRetirementPath,
+            'forbidden_platform_aliases' => $this->forbiddenPlatformAliases,
+        ];
+    }
+
+    /**
+     * @param  iterable<mixed>  $values
+     * @return list<string>
+     */
+    private static function stringList(iterable $values): array
+    {
+        return collect($values)
+            ->filter(static fn (mixed $value): bool => is_string($value) && trim($value) !== '')
+            ->map(static fn (string $value): string => trim($value))
+            ->values()
+            ->all();
+    }
+}

apps/platform/app/Support/Governance/RegistryOwnershipDescriptor.php

@@ -0,0 +1,87 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Support\Governance;
+
+use InvalidArgumentException;
+
+final readonly class RegistryOwnershipDescriptor
+{
+    /**
+     * @param  list<string>  $canonicalNouns
+     * @param  list<string>  $allowedConsumers
+     */
+    public function __construct(
+        public string $registryKey,
+        public string $boundaryClassification,
+        public string $ownerLayer,
+        public string $sourceClassOrFile,
+        public array $canonicalNouns,
+        public array $allowedConsumers,
+        public ?string $compatibilityNotes = null,
+    ) {
+        if (trim($this->registryKey) === '' || trim($this->sourceClassOrFile) === '') {
+            throw new InvalidArgumentException('Registry ownership descriptors require a registry key and source reference.');
+        }
+
+        if ($this->canonicalNouns === [] || $this->allowedConsumers === []) {
+            throw new InvalidArgumentException('Registry ownership descriptors require canonical nouns and allowed consumers.');
+        }
+    }
+
+    /**
+     * @param  array<string, mixed>  $data
+     */
+    public static function fromArray(array $data): self
+    {
+        return new self(
+            registryKey: (string) ($data['registry_key'] ?? ''),
+            boundaryClassification: (string) ($data['boundary_classification'] ?? ''),
+            ownerLayer: (string) ($data['owner_layer'] ?? ''),
+            sourceClassOrFile: (string) ($data['source_class_or_file'] ?? ''),
+            canonicalNouns: self::stringList($data['canonical_nouns'] ?? []),
+            allowedConsumers: self::stringList($data['allowed_consumers'] ?? []),
+            compatibilityNotes: is_string($data['compatibility_notes'] ?? null)
+                ? trim((string) $data['compatibility_notes'])
+                : null,
+        );
+    }
+
+    /**
+     * @return array{
+     *     registry_key: string,
+     *     boundary_classification: string,
+     *     owner_layer: string,
+     *     source_class_or_file: string,
+     *     canonical_nouns: list<string>,
+     *     allowed_consumers: list<string>,
+     *     compatibility_notes: ?string
+     * }
+     */
+    public function toArray(): array
+    {
+        return [
+            'registry_key' => $this->registryKey,
+            'boundary_classification' => $this->boundaryClassification,
+            'owner_layer' => $this->ownerLayer,
+            'source_class_or_file' => $this->sourceClassOrFile,
+            'canonical_nouns' => $this->canonicalNouns,
+            'allowed_consumers' => $this->allowedConsumers,
+            'compatibility_notes' => $this->compatibilityNotes,
+        ];
+    }
+
+    /**
+     * @param  iterable<mixed>  $values
+     * @return list<string>
+     */
+    private static function stringList(iterable $values): array
+    {
+        return collect($values)
+            ->filter(static fn (mixed $value): bool => is_string($value) && trim($value) !== '')
+            ->map(static fn (string $value): string => trim($value))
+            ->values()
+            ->all();
+    }
+}

apps/platform/app/Support/Governance/SubjectDescriptorNormalizationResult.php

@@ -0,0 +1,45 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Support\Governance;
+
+final readonly class SubjectDescriptorNormalizationResult
+{
+    /**
+     * @param  list<string>  $warnings
+     */
+    public function __construct(
+        public PlatformSubjectDescriptor $descriptor,
+        public string $sourceSurface,
+        public bool $usedLegacyAlias = false,
+        public array $warnings = [],
+    ) {}
+
+    /**
+     * @return array{
+     *     descriptor: array{
+     *         domain_key: string,
+     *         subject_class: string,
+     *         subject_type_key: string,
+     *         subject_type_label: string,
+     *         platform_noun: string,
+     *         display_label: string,
+     *         legacy_policy_type: ?string,
+     *         owner_layer: string
+     *     },
+     *     source_surface: string,
+     *     used_legacy_alias: bool,
+     *     warnings: list<string>
+     * }
+     */
+    public function toArray(): array
+    {
+        return [
+            'descriptor' => $this->descriptor->toArray(),
+            'source_surface' => $this->sourceSurface,
+            'used_legacy_alias' => $this->usedLegacyAlias,
+            'warnings' => $this->warnings,
+        ];
+    }
+}

apps/platform/app/Support/OperationCatalog.php

@@ -1,7 +1,11 @@
 <?php
 
+declare(strict_types=1);
+
 namespace App\Support;
 
+use App\Support\Governance\PlatformVocabularyGlossary;
+use App\Support\Governance\RegistryOwnershipDescriptor;
 use App\Support\OpsUx\OperationSummaryKeys;
 
 final class OperationCatalog
@@ -13,51 +17,34 @@ final class OperationCatalog
      */
     public static function labels(): array
     {
-        return [
-            'policy.sync' => 'Policy sync',
-            'policy.sync_one' => 'Policy sync',
-            'policy.capture_snapshot' => 'Policy snapshot',
-            'policy.delete' => 'Delete policies',
-            'policy.unignore' => 'Restore policies',
-            'policy.export' => 'Export policies to backup',
-            'provider.connection.check' => 'Provider connection check',
-            'inventory_sync' => 'Inventory sync',
-            'compliance.snapshot' => 'Compliance snapshot',
-            'provider.inventory.sync' => 'Inventory sync',
-            'provider.compliance.snapshot' => 'Compliance snapshot',
-            'entra_group_sync' => 'Directory groups sync',
-            'backup_set.add_policies' => 'Backup set update',
-            'backup_set.remove_policies' => 'Backup set update',
-            'backup_set.delete' => 'Archive backup sets',
-            'backup_set.restore' => 'Restore backup sets',
-            'backup_set.force_delete' => 'Delete backup sets',
-            'backup_schedule_run' => 'Backup schedule run',
-            'backup_schedule_retention' => 'Backup schedule retention',
-            'backup_schedule_purge' => 'Backup schedule purge',
-            'restore.execute' => 'Restore execution',
-            'assignments.fetch' => 'Assignment fetch',
-            'assignments.restore' => 'Assignment restore',
-            'ops.reconcile_adapter_runs' => 'Reconcile adapter runs',
-            'directory_role_definitions.sync' => 'Role definitions sync',
-            'restore_run.delete' => 'Delete restore runs',
-            'restore_run.restore' => 'Restore restore runs',
-            'restore_run.force_delete' => 'Force delete restore runs',
-            'tenant.sync' => 'Tenant sync',
-            'policy_version.prune' => 'Prune policy versions',
-            'policy_version.restore' => 'Restore policy versions',
-            'policy_version.force_delete' => 'Delete policy versions',
-            'alerts.evaluate' => 'Alerts evaluation',
-            'alerts.deliver' => 'Alerts delivery',
-            'baseline_capture' => 'Baseline capture',
-            'baseline_compare' => 'Baseline compare',
-            'permission_posture_check' => 'Permission posture check',
-            'entra.admin_roles.scan' => 'Entra admin roles scan',
-            'tenant.review_pack.generate' => 'Review pack generation',
-            'tenant.review.compose' => 'Review composition',
-            'tenant.evidence.snapshot.generate' => 'Evidence snapshot generation',
-            'rbac.health_check' => 'RBAC health check',
-            'findings.lifecycle.backfill' => 'Findings lifecycle backfill',
-        ];
+        $labels = [];
+
+        foreach (self::operationAliases() as $alias) {
+            $labels[$alias->rawValue] = self::canonicalDefinitions()[$alias->canonicalCode]->displayLabel;
+        }
+
+        return $labels;
+    }
+
+    /**
+     * @return array<string, array{
+     *     canonical_code: string,
+     *     domain_key: ?string,
+     *     artifact_family: ?string,
+     *     display_label: string,
+     *     supports_operator_explanation: bool,
+     *     expected_duration_seconds: ?int
+     * }>
+     */
+    public static function canonicalInventory(): array
+    {
+        $inventory = [];
+
+        foreach (self::canonicalDefinitions() as $canonicalCode => $definition) {
+            $inventory[$canonicalCode] = $definition->toArray();
+        }
+
+        return $inventory;
     }
 
     public static function label(string $operationType): string
@@ -68,34 +55,12 @@ public static function label(string $operationType): string
             return 'Operation';
         }
 
-        return self::labels()[$operationType] ?? 'Unknown operation';
+        return self::resolve($operationType)->canonical->displayLabel;
     }
 
     public static function expectedDurationSeconds(string $operationType): ?int
     {
-        return match (trim($operationType)) {
-            'policy.sync', 'policy.sync_one' => 90,
-            'provider.connection.check' => 30,
-            'policy.export' => 120,
-            'inventory_sync' => 180,
-            'compliance.snapshot' => 180,
-            'provider.inventory.sync' => 180,
-            'provider.compliance.snapshot' => 180,
-            'entra_group_sync' => 120,
-            'assignments.fetch', 'assignments.restore' => 60,
-            'ops.reconcile_adapter_runs' => 120,
-            'alerts.evaluate', 'alerts.deliver' => 120,
-            'baseline_capture' => 120,
-            'baseline_compare' => 120,
-            'permission_posture_check' => 30,
-            'entra.admin_roles.scan' => 60,
-            'tenant.review_pack.generate' => 60,
-            'tenant.review.compose' => 60,
-            'tenant.evidence.snapshot.generate' => 120,
-            'rbac.health_check' => 30,
-            'findings.lifecycle.backfill' => 300,
-            default => null,
-        };
+        return self::resolve($operationType)->canonical->expectedDurationSeconds;
     }
 
     /**
@@ -108,13 +73,7 @@ public static function allowedSummaryKeys(): array
 
     public static function governanceArtifactFamily(string $operationType): ?string
     {
-        return match (trim($operationType)) {
-            'baseline_capture' => 'baseline_snapshot',
-            'tenant.evidence.snapshot.generate' => 'evidence_snapshot',
-            'tenant.review.compose' => 'tenant_review',
-            'tenant.review_pack.generate' => 'review_pack',
-            default => null,
-        };
+        return self::resolve($operationType)->canonical->artifactFamily;
     }
 
     public static function isGovernanceArtifactOperation(string $operationType): bool
@@ -124,9 +83,227 @@ public static function isGovernanceArtifactOperation(string $operationType): boo
 
     public static function supportsOperatorExplanation(string $operationType): bool
     {
-        $operationType = trim($operationType);
+        return self::resolve($operationType)->canonical->supportsOperatorExplanation;
+    }
 
-        return self::isGovernanceArtifactOperation($operationType)
-            || $operationType === 'baseline_compare';
+    public static function canonicalCode(string $operationType): string
+    {
+        return self::resolve($operationType)->canonical->canonicalCode;
+    }
+
+    /**
+     * @return list<string>
+     */
+    public static function canonicalNouns(): array
+    {
+        return ['operation_type'];
+    }
+
+    public static function ownershipDescriptor(?PlatformVocabularyGlossary $glossary = null): RegistryOwnershipDescriptor
+    {
+        $glossary ??= app(PlatformVocabularyGlossary::class);
+
+        return $glossary->registry('operation_catalog')
+            ?? RegistryOwnershipDescriptor::fromArray([
+                'registry_key' => 'operation_catalog',
+                'boundary_classification' => PlatformVocabularyGlossary::BOUNDARY_PLATFORM_CORE,
+                'owner_layer' => PlatformVocabularyGlossary::OWNER_PLATFORM_CORE,
+                'source_class_or_file' => self::class,
+                'canonical_nouns' => self::canonicalNouns(),
+                'allowed_consumers' => ['monitoring', 'reporting', 'launch_surfaces', 'audit'],
+                'compatibility_notes' => 'Resolves canonical operation meaning from historical storage values without treating every stored raw string as equally canonical.',
+            ]);
+    }
+
+    public static function boundaryClassification(?PlatformVocabularyGlossary $glossary = null): string
+    {
+        return self::ownershipDescriptor($glossary)->boundaryClassification;
+    }
+
+    /**
+     * @return list<string>
+     */
+    public static function rawValuesForCanonical(string $canonicalCode): array
+    {
+        return array_values(array_map(
+            static fn (OperationTypeAlias $alias): string => $alias->rawValue,
+            array_filter(
+                self::operationAliases(),
+                static fn (OperationTypeAlias $alias): bool => $alias->canonicalCode === trim($canonicalCode),
+            ),
+        ));
+    }
+
+    /**
+     * @param  iterable<mixed>|null  $types
+     * @return array<string, string>
+     */
+    public static function filterOptions(?iterable $types = null): array
+    {
+        $values = collect($types ?? array_keys(self::labels()))
+            ->filter(static fn (mixed $type): bool => is_string($type) && trim($type) !== '')
+            ->map(static fn (string $type): string => trim($type))
+            ->mapWithKeys(static fn (string $type): array => [self::canonicalCode($type) => self::label($type)])
+            ->sortBy(static fn (string $label): string => $label)
+            ->all();
+
+        return $values;
+    }
+
+    /**
+     * @return array<string, array{
+     *     raw_value: string,
+     *     canonical_name: string,
+     *     alias_status: string,
+     *     write_allowed: bool,
+     *     deprecation_note: ?string,
+     *     retirement_path: ?string
+     * }>
+     */
+    public static function aliasInventory(): array
+    {
+        $inventory = [];
+
+        foreach (self::operationAliases() as $alias) {
+            $inventory[$alias->rawValue] = $alias->retirementMetadata();
+        }
+
+        return $inventory;
+    }
+
+    public static function resolve(string $operationType): OperationTypeResolution
+    {
+        $operationType = trim($operationType);
+        $aliases = self::operationAliases();
+        $matchedAlias = collect($aliases)
+            ->first(static fn (OperationTypeAlias $alias): bool => $alias->rawValue === $operationType);
+
+        if ($matchedAlias instanceof OperationTypeAlias) {
+            return new OperationTypeResolution(
+                rawValue: $operationType,
+                canonical: self::canonicalDefinitions()[$matchedAlias->canonicalCode],
+                aliasesConsidered: array_values(array_filter(
+                    $aliases,
+                    static fn (OperationTypeAlias $alias): bool => $alias->canonicalCode === $matchedAlias->canonicalCode,
+                )),
+                aliasStatus: $matchedAlias->aliasStatus,
+                wasLegacyAlias: $matchedAlias->aliasStatus !== 'canonical',
+            );
+        }
+
+        return new OperationTypeResolution(
+            rawValue: $operationType,
+            canonical: new CanonicalOperationType(
+                canonicalCode: $operationType,
+                domainKey: null,
+                artifactFamily: null,
+                displayLabel: 'Unknown operation',
+                supportsOperatorExplanation: false,
+                expectedDurationSeconds: null,
+            ),
+            aliasesConsidered: [],
+            aliasStatus: 'unknown',
+            wasLegacyAlias: false,
+        );
+    }
+
+    /**
+     * @return array<string, CanonicalOperationType>
+     */
+    private static function canonicalDefinitions(): array
+    {
+        return [
+            'policy.sync' => new CanonicalOperationType('policy.sync', 'intune', null, 'Policy sync', false, 90),
+            'policy.snapshot' => new CanonicalOperationType('policy.snapshot', 'intune', null, 'Policy snapshot', false, 120),
+            'policy.delete' => new CanonicalOperationType('policy.delete', 'intune', null, 'Delete policies'),
+            'policy.restore' => new CanonicalOperationType('policy.restore', 'intune', null, 'Restore policies'),
+            'policy.export' => new CanonicalOperationType('policy.export', 'intune', null, 'Export policies to backup', false, 120),
+            'provider.connection.check' => new CanonicalOperationType('provider.connection.check', 'intune', null, 'Provider connection check', false, 30),
+            'inventory.sync' => new CanonicalOperationType('inventory.sync', 'intune', null, 'Inventory sync', false, 180),
+            'compliance.snapshot' => new CanonicalOperationType('compliance.snapshot', 'intune', null, 'Compliance snapshot', false, 180),
+            'directory.groups.sync' => new CanonicalOperationType('directory.groups.sync', 'entra', null, 'Directory groups sync', false, 120),
+            'backup_set.update' => new CanonicalOperationType('backup_set.update', 'intune', null, 'Backup set update'),
+            'backup_set.archive' => new CanonicalOperationType('backup_set.archive', 'intune', null, 'Archive backup sets'),
+            'backup_set.restore' => new CanonicalOperationType('backup_set.restore', 'intune', null, 'Restore backup sets'),
+            'backup_set.delete' => new CanonicalOperationType('backup_set.delete', 'intune', null, 'Delete backup sets'),
+            'backup.schedule.execute' => new CanonicalOperationType('backup.schedule.execute', 'intune', null, 'Backup schedule run'),
+            'backup.schedule.retention' => new CanonicalOperationType('backup.schedule.retention', 'intune', null, 'Backup schedule retention'),
+            'backup.schedule.purge' => new CanonicalOperationType('backup.schedule.purge', 'intune', null, 'Backup schedule purge'),
+            'restore.execute' => new CanonicalOperationType('restore.execute', 'intune', null, 'Restore execution'),
+            'assignments.fetch' => new CanonicalOperationType('assignments.fetch', 'intune', null, 'Assignment fetch', false, 60),
+            'assignments.restore' => new CanonicalOperationType('assignments.restore', 'intune', null, 'Assignment restore', false, 60),
+            'ops.reconcile_adapter_runs' => new CanonicalOperationType('ops.reconcile_adapter_runs', 'platform_foundation', null, 'Reconcile adapter runs', false, 120),
+            'directory.role_definitions.sync' => new CanonicalOperationType('directory.role_definitions.sync', 'entra', null, 'Role definitions sync'),
+            'restore_run.delete' => new CanonicalOperationType('restore_run.delete', 'intune', null, 'Delete restore runs'),
+            'restore_run.restore' => new CanonicalOperationType('restore_run.restore', 'intune', null, 'Restore restore runs'),
+            'restore_run.force_delete' => new CanonicalOperationType('restore_run.force_delete', 'intune', null, 'Force delete restore runs'),
+            'tenant.sync' => new CanonicalOperationType('tenant.sync', 'platform_foundation', null, 'Tenant sync'),
+            'policy_version.prune' => new CanonicalOperationType('policy_version.prune', 'intune', null, 'Prune policy versions'),
+            'policy_version.restore' => new CanonicalOperationType('policy_version.restore', 'intune', null, 'Restore policy versions'),
+            'policy_version.force_delete' => new CanonicalOperationType('policy_version.force_delete', 'intune', null, 'Delete policy versions'),
+            'alerts.evaluate' => new CanonicalOperationType('alerts.evaluate', 'platform_foundation', null, 'Alerts evaluation', false, 120),
+            'alerts.deliver' => new CanonicalOperationType('alerts.deliver', 'platform_foundation', null, 'Alerts delivery', false, 120),
+            'baseline.capture' => new CanonicalOperationType('baseline.capture', 'platform_foundation', 'baseline_snapshot', 'Baseline capture', true, 120),
+            'baseline.compare' => new CanonicalOperationType('baseline.compare', 'platform_foundation', null, 'Baseline compare', true, 120),
+            'permission.posture.check' => new CanonicalOperationType('permission.posture.check', 'platform_foundation', null, 'Permission posture check', false, 30),
+            'entra.admin_roles.scan' => new CanonicalOperationType('entra.admin_roles.scan', 'entra', null, 'Entra admin roles scan', false, 60),
+            'tenant.review_pack.generate' => new CanonicalOperationType('tenant.review_pack.generate', 'platform_foundation', 'review_pack', 'Review pack generation', true, 60),
+            'tenant.review.compose' => new CanonicalOperationType('tenant.review.compose', 'platform_foundation', 'tenant_review', 'Review composition', true, 60),
+            'tenant.evidence.snapshot.generate' => new CanonicalOperationType('tenant.evidence.snapshot.generate', 'platform_foundation', 'evidence_snapshot', 'Evidence snapshot generation', true, 120),
+            'rbac.health_check' => new CanonicalOperationType('rbac.health_check', 'intune', null, 'RBAC health check', false, 30),
+            'findings.lifecycle.backfill' => new CanonicalOperationType('findings.lifecycle.backfill', 'platform_foundation', null, 'Findings lifecycle backfill', false, 300),
+        ];
+    }
+
+    /**
+     * @return list<OperationTypeAlias>
+     */
+    private static function operationAliases(): array
+    {
+        return [
+            new OperationTypeAlias('policy.sync', 'policy.sync', 'canonical', true),
+            new OperationTypeAlias('policy.sync_one', 'policy.sync', 'legacy_alias', true, 'Legacy single-policy sync values resolve to the canonical policy.sync operation.', 'Prefer policy.sync on platform-owned read paths.'),
+            new OperationTypeAlias('policy.capture_snapshot', 'policy.snapshot', 'canonical', true),
+            new OperationTypeAlias('policy.delete', 'policy.delete', 'canonical', true),
+            new OperationTypeAlias('policy.unignore', 'policy.restore', 'legacy_alias', true, 'Legacy policy.unignore values resolve to policy.restore for operator-facing wording.', 'Prefer policy.restore on new platform-owned read models.'),
+            new OperationTypeAlias('policy.export', 'policy.export', 'canonical', true),
+            new OperationTypeAlias('provider.connection.check', 'provider.connection.check', 'canonical', true),
+            new OperationTypeAlias('inventory_sync', 'inventory.sync', 'legacy_alias', true, 'Legacy inventory_sync storage values resolve to the canonical inventory.sync operation.', 'Preserve stored values during rollout while showing inventory.sync semantics on read paths.'),
+            new OperationTypeAlias('provider.inventory.sync', 'inventory.sync', 'legacy_alias', false, 'Provider-prefixed historical inventory sync values share the same operator meaning as inventory sync.', 'Avoid emitting provider.inventory.sync on new platform-owned surfaces.'),
+            new OperationTypeAlias('compliance.snapshot', 'compliance.snapshot', 'canonical', true),
+            new OperationTypeAlias('provider.compliance.snapshot', 'compliance.snapshot', 'legacy_alias', false, 'Provider-prefixed compliance snapshot values resolve to the canonical compliance.snapshot operation.', 'Avoid emitting provider.compliance.snapshot on new platform-owned surfaces.'),
+            new OperationTypeAlias('entra_group_sync', 'directory.groups.sync', 'legacy_alias', true, 'Historical entra_group_sync values resolve to directory.groups.sync.', 'Prefer directory.groups.sync on new platform-owned read models.'),
+            new OperationTypeAlias('backup_set.add_policies', 'backup_set.update', 'canonical', true),
+            new OperationTypeAlias('backup_set.remove_policies', 'backup_set.update', 'legacy_alias', true, 'Removal and addition both resolve to the same backup-set update operator meaning.', 'Use backup_set.update for canonical reporting buckets.'),
+            new OperationTypeAlias('backup_set.delete', 'backup_set.archive', 'canonical', true),
+            new OperationTypeAlias('backup_set.restore', 'backup_set.restore', 'canonical', true),
+            new OperationTypeAlias('backup_set.force_delete', 'backup_set.delete', 'legacy_alias', true, 'Force-delete wording is normalized to the canonical delete label.', 'Use backup_set.delete for new platform-owned summaries.'),
+            new OperationTypeAlias('backup_schedule_run', 'backup.schedule.execute', 'legacy_alias', true, 'Historical backup_schedule_run values resolve to backup.schedule.execute.', 'Prefer backup.schedule.execute on canonical read paths.'),
+            new OperationTypeAlias('backup_schedule_retention', 'backup.schedule.retention', 'legacy_alias', true, 'Legacy backup schedule retention values resolve to backup.schedule.retention.', 'Prefer dotted canonical backup schedule naming on new read paths.'),
+            new OperationTypeAlias('backup_schedule_purge', 'backup.schedule.purge', 'legacy_alias', true, 'Legacy backup schedule purge values resolve to backup.schedule.purge.', 'Prefer dotted canonical backup schedule naming on new read paths.'),
+            new OperationTypeAlias('restore.execute', 'restore.execute', 'canonical', true),
+            new OperationTypeAlias('assignments.fetch', 'assignments.fetch', 'canonical', true),
+            new OperationTypeAlias('assignments.restore', 'assignments.restore', 'canonical', true),
+            new OperationTypeAlias('ops.reconcile_adapter_runs', 'ops.reconcile_adapter_runs', 'canonical', true),
+            new OperationTypeAlias('directory_role_definitions.sync', 'directory.role_definitions.sync', 'legacy_alias', true, 'Legacy directory_role_definitions.sync values resolve to directory.role_definitions.sync.', 'Prefer dotted role-definition naming on new read paths.'),
+            new OperationTypeAlias('restore_run.delete', 'restore_run.delete', 'canonical', true),
+            new OperationTypeAlias('restore_run.restore', 'restore_run.restore', 'canonical', true),
+            new OperationTypeAlias('restore_run.force_delete', 'restore_run.force_delete', 'canonical', true),
+            new OperationTypeAlias('tenant.sync', 'tenant.sync', 'canonical', true),
+            new OperationTypeAlias('policy_version.prune', 'policy_version.prune', 'canonical', true),
+            new OperationTypeAlias('policy_version.restore', 'policy_version.restore', 'canonical', true),
+            new OperationTypeAlias('policy_version.force_delete', 'policy_version.force_delete', 'canonical', true),
+            new OperationTypeAlias('alerts.evaluate', 'alerts.evaluate', 'canonical', true),
+            new OperationTypeAlias('alerts.deliver', 'alerts.deliver', 'canonical', true),
+            new OperationTypeAlias('baseline_capture', 'baseline.capture', 'legacy_alias', true, 'Historical baseline_capture values resolve to baseline.capture.', 'Prefer baseline.capture on canonical read paths.'),
+            new OperationTypeAlias('baseline_compare', 'baseline.compare', 'legacy_alias', true, 'Historical baseline_compare values resolve to baseline.compare.', 'Prefer baseline.compare on canonical read paths.'),
+            new OperationTypeAlias('permission_posture_check', 'permission.posture.check', 'legacy_alias', true, 'Historical permission_posture_check values resolve to permission.posture.check.', 'Prefer dotted permission posture naming on new read paths.'),
+            new OperationTypeAlias('entra.admin_roles.scan', 'entra.admin_roles.scan', 'canonical', true),
+            new OperationTypeAlias('tenant.review_pack.generate', 'tenant.review_pack.generate', 'canonical', true),
+            new OperationTypeAlias('tenant.review.compose', 'tenant.review.compose', 'canonical', true),
+            new OperationTypeAlias('tenant.evidence.snapshot.generate', 'tenant.evidence.snapshot.generate', 'canonical', true),
+            new OperationTypeAlias('rbac.health_check', 'rbac.health_check', 'canonical', true),
+            new OperationTypeAlias('findings.lifecycle.backfill', 'findings.lifecycle.backfill', 'canonical', true),
+        ];
     }
 }

apps/platform/app/Support/OperationRunType.php

@@ -27,4 +27,26 @@ public static function values(): array
     {
         return array_map(static fn (self $case): string => $case->value, self::cases());
     }
+
+    public function canonicalCode(): string
+    {
+        return match ($this) {
+            self::BaselineCapture => 'baseline.capture',
+            self::BaselineCompare => 'baseline.compare',
+            self::InventorySync => 'inventory.sync',
+            self::PolicySync, self::PolicySyncOne => 'policy.sync',
+            self::DirectoryGroupsSync => 'directory.groups.sync',
+            self::BackupScheduleExecute => 'backup.schedule.execute',
+            self::BackupScheduleRetention => 'backup.schedule.retention',
+            self::BackupSchedulePurge => 'backup.schedule.purge',
+            self::DirectoryRoleDefinitionsSync => 'directory.role_definitions.sync',
+            self::RestoreExecute => 'restore.execute',
+            self::EntraAdminRolesScan => 'entra.admin_roles.scan',
+            self::ReviewPackGenerate => 'tenant.review_pack.generate',
+            self::TenantReviewCompose => 'tenant.review.compose',
+            self::EvidenceSnapshotGenerate => 'tenant.evidence.snapshot.generate',
+            self::RbacHealthCheck => 'rbac.health_check',
+            default => $this->value,
+        };
+    }
 }

apps/platform/app/Support/OperationTypeAlias.php

@@ -0,0 +1,72 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Support;
+
+use InvalidArgumentException;
+
+final readonly class OperationTypeAlias
+{
+    public function __construct(
+        public string $rawValue,
+        public string $canonicalCode,
+        public string $aliasStatus,
+        public bool $writeAllowed,
+        public ?string $deprecationNote = null,
+        public ?string $retirementPath = null,
+    ) {
+        if (trim($this->rawValue) === '' || trim($this->canonicalCode) === '') {
+            throw new InvalidArgumentException('Operation type aliases require a raw value and canonical code.');
+        }
+    }
+
+    /**
+     * @return array{
+     *     raw_value: string,
+     *     canonical_code: string,
+     *     alias_status: string,
+     *     write_allowed: bool,
+     *     deprecation_note: ?string,
+     *     retirement_path: ?string
+     * }
+     */
+    public function toArray(): array
+    {
+        return [
+            'raw_value' => $this->rawValue,
+            'canonical_code' => $this->canonicalCode,
+            'alias_status' => $this->aliasStatus,
+            'write_allowed' => $this->writeAllowed,
+            'deprecation_note' => $this->deprecationNote,
+            'retirement_path' => $this->retirementPath,
+        ];
+    }
+
+    public function canonicalName(): string
+    {
+        return $this->canonicalCode;
+    }
+
+    /**
+     * @return array{
+     *     raw_value: string,
+     *     canonical_name: string,
+     *     alias_status: string,
+     *     write_allowed: bool,
+     *     deprecation_note: ?string,
+     *     retirement_path: ?string
+     * }
+     */
+    public function retirementMetadata(): array
+    {
+        return [
+            'raw_value' => $this->rawValue,
+            'canonical_name' => $this->canonicalName(),
+            'alias_status' => $this->aliasStatus,
+            'write_allowed' => $this->writeAllowed,
+            'deprecation_note' => $this->deprecationNote,
+            'retirement_path' => $this->retirementPath,
+        ];
+    }
+}

apps/platform/app/Support/OperationTypeResolution.php

@@ -0,0 +1,56 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Support;
+
+final readonly class OperationTypeResolution
+{
+    /**
+     * @param  list<OperationTypeAlias>  $aliasesConsidered
+     */
+    public function __construct(
+        public string $rawValue,
+        public CanonicalOperationType $canonical,
+        public array $aliasesConsidered,
+        public string $aliasStatus,
+        public bool $wasLegacyAlias,
+    ) {}
+
+    /**
+     * @return array{
+     *     raw_value: string,
+     *     canonical: array{
+     *         canonical_code: string,
+     *         domain_key: ?string,
+     *         artifact_family: ?string,
+     *         display_label: string,
+     *         supports_operator_explanation: bool,
+     *         expected_duration_seconds: ?int
+     *     },
+     *     aliases_considered: list<array{
+     *         raw_value: string,
+     *         canonical_code: string,
+     *         alias_status: string,
+     *         write_allowed: bool,
+     *         deprecation_note: ?string,
+     *         retirement_path: ?string
+     *     }>,
+     *     alias_status: string,
+     *     was_legacy_alias: bool
+     * }
+     */
+    public function toArray(): array
+    {
+        return [
+            'raw_value' => $this->rawValue,
+            'canonical' => $this->canonical->toArray(),
+            'aliases_considered' => array_map(
+                static fn (OperationTypeAlias $alias): array => $alias->toArray(),
+                $this->aliasesConsidered,
+            ),
+            'alias_status' => $this->aliasStatus,
+            'was_legacy_alias' => $this->wasLegacyAlias,
+        ];
+    }
+}

apps/platform/app/Support/Operations/ExecutionDenialReasonCode.php

@@ -5,6 +5,8 @@
 namespace App\Support\Operations;
 
 use App\Support\ReasonTranslation\NextStepOption;
+use App\Support\ReasonTranslation\PlatformReasonFamily;
+use App\Support\ReasonTranslation\ReasonOwnershipDescriptor;
 use App\Support\ReasonTranslation\ReasonResolutionEnvelope;
 
 enum ExecutionDenialReasonCode: string
@@ -125,6 +127,12 @@ public function toReasonResolutionEnvelope(string $surface = 'detail', array $co
             nextSteps: $this->nextSteps(),
             showNoActionNeeded: false,
             diagnosticCodeLabel: $this->value,
+            reasonOwnership: new ReasonOwnershipDescriptor(
+                ownerLayer: 'platform_core',
+                ownerNamespace: 'execution_denial',
+                reasonCode: $this->value,
+                platformReasonFamily: PlatformReasonFamily::Authorization,
+            ),
         );
     }
 }

apps/platform/app/Support/Operations/LifecycleReconciliationReason.php

@@ -5,6 +5,8 @@
 namespace App\Support\Operations;
 
 use App\Support\ReasonTranslation\NextStepOption;
+use App\Support\ReasonTranslation\PlatformReasonFamily;
+use App\Support\ReasonTranslation\ReasonOwnershipDescriptor;
 use App\Support\ReasonTranslation\ReasonResolutionEnvelope;
 
 enum LifecycleReconciliationReason: string
@@ -78,6 +80,12 @@ public function toReasonResolutionEnvelope(string $surface = 'detail', array $co
             nextSteps: $this->nextSteps(),
             showNoActionNeeded: false,
             diagnosticCodeLabel: $this->value,
+            reasonOwnership: new ReasonOwnershipDescriptor(
+                ownerLayer: 'platform_core',
+                ownerNamespace: 'operation_lifecycle',
+                reasonCode: $this->value,
+                platformReasonFamily: PlatformReasonFamily::Execution,
+            ),
         );
     }
 }

apps/platform/app/Support/Providers/ProviderReasonCodes.php

@@ -2,6 +2,10 @@
 
 namespace App\Support\Providers;
 
+use App\Support\Governance\PlatformVocabularyGlossary;
+use App\Support\ReasonTranslation\PlatformReasonFamily;
+use App\Support\ReasonTranslation\ReasonOwnershipDescriptor;
+
 final class ProviderReasonCodes
 {
     public const string ProviderConnectionMissing = 'provider_connection_missing';
@@ -92,4 +96,65 @@ public static function isKnown(string $reasonCode): bool
     {
         return in_array($reasonCode, self::all(), true) || str_starts_with($reasonCode, 'ext.');
     }
+
+    public static function registryKey(): string
+    {
+        return 'provider_reason_codes';
+    }
+
+    /**
+     * @return list<string>
+     */
+    public static function canonicalNouns(): array
+    {
+        return ['reason_code'];
+    }
+
+    public static function ownerLayer(string $reasonCode): string
+    {
+        return PlatformVocabularyGlossary::OWNER_PROVIDER_OWNED;
+    }
+
+    public static function boundaryClassification(string $reasonCode): string
+    {
+        return PlatformVocabularyGlossary::BOUNDARY_INTUNE_SPECIFIC;
+    }
+
+    public static function ownerNamespace(string $reasonCode): string
+    {
+        return str_starts_with($reasonCode, 'intune_rbac.')
+            ? 'provider.intune_rbac'
+            : 'provider.microsoft_graph';
+    }
+
+    public static function platformReasonFamily(string $reasonCode): PlatformReasonFamily
+    {
+        return match ($reasonCode) {
+            self::ProviderPermissionMissing,
+            self::ProviderPermissionDenied,
+            self::IntuneRbacPermissionMissing => PlatformReasonFamily::Authorization,
+            self::NetworkUnreachable,
+            self::RateLimited,
+            self::ProviderPermissionRefreshFailed,
+            self::ProviderAuthFailed => PlatformReasonFamily::Availability,
+            self::ProviderConnectionTypeInvalid,
+            self::TenantTargetMismatch,
+            self::ProviderConnectionReviewRequired => PlatformReasonFamily::Compatibility,
+            default => PlatformReasonFamily::Prerequisite,
+        };
+    }
+
+    public static function ownershipDescriptor(string $reasonCode): ?ReasonOwnershipDescriptor
+    {
+        if (! self::isKnown($reasonCode)) {
+            return null;
+        }
+
+        return new ReasonOwnershipDescriptor(
+            ownerLayer: self::ownerLayer($reasonCode),
+            ownerNamespace: self::ownerNamespace($reasonCode),
+            reasonCode: $reasonCode,
+            platformReasonFamily: self::platformReasonFamily($reasonCode),
+        );
+    }
 }

apps/platform/app/Support/Providers/ProviderReasonTranslator.php

@@ -248,6 +248,7 @@ private function envelope(
             nextSteps: $nextSteps,
             showNoActionNeeded: false,
             diagnosticCodeLabel: $reasonCode,
+            reasonOwnership: ProviderReasonCodes::ownershipDescriptor($reasonCode),
         );
     }
 

apps/platform/app/Support/RbacReason.php

@@ -2,7 +2,10 @@
 
 namespace App\Support;
 
+use App\Support\Governance\PlatformVocabularyGlossary;
 use App\Support\ReasonTranslation\NextStepOption;
+use App\Support\ReasonTranslation\PlatformReasonFamily;
+use App\Support\ReasonTranslation\ReasonOwnershipDescriptor;
 use App\Support\ReasonTranslation\ReasonResolutionEnvelope;
 
 enum RbacReason: string
@@ -60,6 +63,26 @@ public function actionability(): string
         };
     }
 
+    public function ownerLayer(): string
+    {
+        return PlatformVocabularyGlossary::OWNER_DOMAIN_OWNED;
+    }
+
+    public function ownerNamespace(): string
+    {
+        return 'rbac.intune';
+    }
+
+    public function platformReasonFamily(): PlatformReasonFamily
+    {
+        return PlatformReasonFamily::Authorization;
+    }
+
+    public function boundaryClassification(): string
+    {
+        return PlatformVocabularyGlossary::BOUNDARY_INTUNE_SPECIFIC;
+    }
+
     /**
      * @return array<int, NextStepOption>
      */
@@ -92,6 +115,12 @@ public function toReasonResolutionEnvelope(string $surface = 'detail', array $co
             nextSteps: $this->nextSteps(),
             showNoActionNeeded: $this->actionability() === 'non_actionable',
             diagnosticCodeLabel: $this->value,
+            reasonOwnership: new ReasonOwnershipDescriptor(
+                ownerLayer: $this->ownerLayer(),
+                ownerNamespace: $this->ownerNamespace(),
+                reasonCode: $this->value,
+                platformReasonFamily: $this->platformReasonFamily(),
+            ),
         );
     }
 }

apps/platform/app/Support/ReasonTranslation/PlatformReasonFamily.php

@@ -0,0 +1,27 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Support\ReasonTranslation;
+
+enum PlatformReasonFamily: string
+{
+    case Authorization = 'authorization';
+    case Prerequisite = 'prerequisite';
+    case Compatibility = 'compatibility';
+    case Coverage = 'coverage';
+    case Availability = 'availability';
+    case Execution = 'execution';
+
+    public function label(): string
+    {
+        return match ($this) {
+            self::Authorization => 'Authorization',
+            self::Prerequisite => 'Prerequisite',
+            self::Compatibility => 'Compatibility',
+            self::Coverage => 'Coverage',
+            self::Availability => 'Availability',
+            self::Execution => 'Execution',
+        };
+    }
+}

apps/platform/app/Support/ReasonTranslation/ReasonOwnershipDescriptor.php

@@ -0,0 +1,62 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Support\ReasonTranslation;
+
+final readonly class ReasonOwnershipDescriptor
+{
+    public function __construct(
+        public string $ownerLayer,
+        public string $ownerNamespace,
+        public string $reasonCode,
+        public PlatformReasonFamily $platformReasonFamily,
+    ) {}
+
+    /**
+     * @param  array<string, mixed>  $data
+     */
+    public static function fromArray(array $data): ?self
+    {
+        $family = is_string($data['platform_reason_family'] ?? null)
+            ? PlatformReasonFamily::tryFrom((string) $data['platform_reason_family'])
+            : null;
+
+        if (! $family instanceof PlatformReasonFamily) {
+            return null;
+        }
+
+        $ownerLayer = is_string($data['owner_layer'] ?? null) ? trim((string) $data['owner_layer']) : '';
+        $ownerNamespace = is_string($data['owner_namespace'] ?? null) ? trim((string) $data['owner_namespace']) : '';
+        $reasonCode = is_string($data['reason_code'] ?? null) ? trim((string) $data['reason_code']) : '';
+
+        if ($ownerLayer === '' || $ownerNamespace === '' || $reasonCode === '') {
+            return null;
+        }
+
+        return new self(
+            ownerLayer: $ownerLayer,
+            ownerNamespace: $ownerNamespace,
+            reasonCode: $reasonCode,
+            platformReasonFamily: $family,
+        );
+    }
+
+    /**
+     * @return array{
+     *     owner_layer: string,
+     *     owner_namespace: string,
+     *     reason_code: string,
+     *     platform_reason_family: string
+     * }
+     */
+    public function toArray(): array
+    {
+        return [
+            'owner_layer' => $this->ownerLayer,
+            'owner_namespace' => $this->ownerNamespace,
+            'reason_code' => $this->reasonCode,
+            'platform_reason_family' => $this->platformReasonFamily->value,
+        ];
+    }
+}

apps/platform/app/Support/ReasonTranslation/ReasonPresenter.php

@@ -13,6 +13,7 @@
 use App\Support\Providers\ProviderReasonTranslator;
 use App\Support\RbacReason;
 use App\Support\Tenants\TenantOperabilityReasonCode;
+use Illuminate\Support\Str;
 
 final class ReasonPresenter
 {
@@ -209,6 +210,93 @@ public function trustImpact(?ReasonResolutionEnvelope $envelope): ?string
         return $envelope?->trustImpact;
     }
 
+    public function ownerLayer(?ReasonResolutionEnvelope $envelope): ?string
+    {
+        return $envelope?->ownerLayer();
+    }
+
+    public function ownerNamespace(?ReasonResolutionEnvelope $envelope): ?string
+    {
+        return $envelope?->ownerNamespace();
+    }
+
+    public function platformReasonFamily(?ReasonResolutionEnvelope $envelope): ?string
+    {
+        return $envelope?->platformReasonFamily();
+    }
+
+    public function platformReasonFamilyLabel(?ReasonResolutionEnvelope $envelope): ?string
+    {
+        return $envelope?->platformReasonFamilyEnum()?->label();
+    }
+
+    public function ownerLabel(?ReasonResolutionEnvelope $envelope): ?string
+    {
+        $ownerNamespace = $envelope?->ownerNamespace();
+
+        if (! is_string($ownerNamespace) || trim($ownerNamespace) === '') {
+            return null;
+        }
+
+        return match (true) {
+            str_starts_with($ownerNamespace, 'provider.') => 'Provider-owned detail',
+            str_starts_with($ownerNamespace, 'governance.') => 'Governance detail',
+            $ownerNamespace === 'rbac.intune' => 'Intune RBAC detail',
+            $ownerNamespace === 'tenant_operability',
+            $ownerNamespace === 'execution_denial',
+            $ownerNamespace === 'operation_lifecycle',
+            $ownerNamespace === 'reason_translation.fallback' => 'Platform core',
+            default => match ($envelope?->ownerLayer()) {
+                'provider_owned' => 'Provider-owned detail',
+                'domain_owned' => 'Domain-owned detail',
+                'platform_core' => 'Platform core',
+                'compatibility_alias' => 'Compatibility alias',
+                'compatibility_only' => 'Compatibility-only detail',
+                default => Str::of((string) $envelope?->ownerLayer())->replace('_', ' ')->headline()->toString(),
+            },
+        };
+    }
+
+    /**
+     * @return array{
+     *     owner_label: string,
+     *     owner_layer: string,
+     *     owner_namespace: string,
+     *     boundary_classification: ?string,
+     *     boundary_label: ?string,
+     *     family: string,
+     *     family_label: string,
+     *     diagnostic_code: string
+     * }|null
+     */
+    public function semantics(?ReasonResolutionEnvelope $envelope): ?array
+    {
+        if (! $envelope instanceof ReasonResolutionEnvelope) {
+            return null;
+        }
+
+        $boundary = $this->reasonTranslator->boundaryClassificationForEnvelope($envelope);
+        $family = $envelope->platformReasonFamilyEnum();
+        $ownerLabel = $this->ownerLabel($envelope);
+
+        if (! is_string($ownerLabel) || $family === null) {
+            return null;
+        }
+
+        return [
+            'owner_label' => $ownerLabel,
+            'owner_layer' => (string) $envelope->ownerLayer(),
+            'owner_namespace' => (string) $envelope->ownerNamespace(),
+            'boundary_classification' => $boundary,
+            'boundary_label' => is_string($boundary)
+                ? Str::of($boundary)->replace('_', ' ')->headline()->toString()
+                : null,
+            'family' => $family->value,
+            'family_label' => $family->label(),
+            'diagnostic_code' => $envelope->diagnosticCode(),
+        ];
+    }
+
     public function absencePattern(?ReasonResolutionEnvelope $envelope): ?string
     {
         return $envelope?->absencePattern;

apps/platform/app/Support/ReasonTranslation/ReasonResolutionEnvelope.php

@@ -22,6 +22,7 @@ public function __construct(
         public ?string $diagnosticCodeLabel = null,
         public string $trustImpact = TrustworthinessLevel::LimitedConfidence->value,
         public ?string $absencePattern = null,
+        public ?ReasonOwnershipDescriptor $reasonOwnership = null,
     ) {
         if (trim($this->internalCode) === '') {
             throw new InvalidArgumentException('Reason envelopes must preserve an internal code.');
@@ -97,6 +98,14 @@ public static function fromArray(array $data): ?self
         $absencePattern = is_string($data['absence_pattern'] ?? null)
             ? trim((string) $data['absence_pattern'])
             : (is_string($data['absencePattern'] ?? null) ? trim((string) $data['absencePattern']) : null);
+        $reasonOwnership = is_array($data['reason_owner'] ?? null)
+            ? ReasonOwnershipDescriptor::fromArray($data['reason_owner'])
+            : (is_array($data['reasonOwnership'] ?? null) ? ReasonOwnershipDescriptor::fromArray($data['reasonOwnership']) : ReasonOwnershipDescriptor::fromArray([
+                'owner_layer' => $data['owner_layer'] ?? $data['ownerLayer'] ?? null,
+                'owner_namespace' => $data['owner_namespace'] ?? $data['ownerNamespace'] ?? null,
+                'reason_code' => $data['reason_code'] ?? $internalCode,
+                'platform_reason_family' => $data['platform_reason_family'] ?? $data['platformReasonFamily'] ?? null,
+            ]));
 
         if ($internalCode === '' || $operatorLabel === '' || $shortExplanation === '' || $actionability === '') {
             return null;
@@ -112,6 +121,7 @@ public static function fromArray(array $data): ?self
             diagnosticCodeLabel: $diagnosticCodeLabel !== '' ? $diagnosticCodeLabel : null,
             trustImpact: $trustImpact !== '' ? $trustImpact : TrustworthinessLevel::LimitedConfidence->value,
             absencePattern: $absencePattern !== '' ? $absencePattern : null,
+            reasonOwnership: $reasonOwnership,
         );
     }
 
@@ -130,6 +140,23 @@ public function withNextSteps(array $nextSteps): self
             diagnosticCodeLabel: $this->diagnosticCodeLabel,
             trustImpact: $this->trustImpact,
             absencePattern: $this->absencePattern,
+            reasonOwnership: $this->reasonOwnership,
+        );
+    }
+
+    public function withReasonOwnership(?ReasonOwnershipDescriptor $reasonOwnership): self
+    {
+        return new self(
+            internalCode: $this->internalCode,
+            operatorLabel: $this->operatorLabel,
+            shortExplanation: $this->shortExplanation,
+            actionability: $this->actionability,
+            nextSteps: $this->nextSteps,
+            showNoActionNeeded: $this->showNoActionNeeded,
+            diagnosticCodeLabel: $this->diagnosticCodeLabel,
+            trustImpact: $this->trustImpact,
+            absencePattern: $this->absencePattern,
+            reasonOwnership: $reasonOwnership,
         );
     }
 
@@ -181,6 +208,26 @@ public function diagnosticCode(): string
             : $this->internalCode;
     }
 
+    public function ownerLayer(): ?string
+    {
+        return $this->reasonOwnership?->ownerLayer;
+    }
+
+    public function ownerNamespace(): ?string
+    {
+        return $this->reasonOwnership?->ownerNamespace;
+    }
+
+    public function platformReasonFamily(): ?string
+    {
+        return $this->reasonOwnership?->platformReasonFamily->value;
+    }
+
+    public function platformReasonFamilyEnum(): ?PlatformReasonFamily
+    {
+        return $this->reasonOwnership?->platformReasonFamily;
+    }
+
     /**
      * @return array<int, array{label: string, url: string}>
      */
@@ -209,9 +256,18 @@ public function toLegacyNextSteps(): array
      *         scope: string
      *     }>,
      *     show_no_action_needed: bool,
-     *     diagnostic_code_label: string
+     *     diagnostic_code_label: string,
      *     trust_impact: string,
-     *     absence_pattern: ?string
+     *     absence_pattern: ?string,
+     *     reason_owner: ?array{
+     *         owner_layer: string,
+     *         owner_namespace: string,
+     *         reason_code: string,
+     *         platform_reason_family: string
+     *     },
+     *     owner_layer: ?string,
+     *     owner_namespace: ?string,
+     *     platform_reason_family: ?string
      * }
      */
     public function toArray(): array
@@ -229,6 +285,10 @@ public function toArray(): array
             'diagnostic_code_label' => $this->diagnosticCode(),
             'trust_impact' => $this->trustImpact,
             'absence_pattern' => $this->absencePattern,
+            'reason_owner' => $this->reasonOwnership?->toArray(),
+            'owner_layer' => $this->ownerLayer(),
+            'owner_namespace' => $this->ownerNamespace(),
+            'platform_reason_family' => $this->platformReasonFamily(),
         ];
     }
 }

apps/platform/app/Support/ReasonTranslation/ReasonTranslator.php

@@ -6,6 +6,7 @@
 
 use App\Support\Baselines\BaselineCompareReasonCode;
 use App\Support\Baselines\BaselineReasonCodes;
+use App\Support\Governance\PlatformVocabularyGlossary;
 use App\Support\Operations\ExecutionDenialReasonCode;
 use App\Support\Operations\LifecycleReconciliationReason;
 use App\Support\Providers\ProviderReasonCodes;
@@ -27,6 +28,7 @@ final class ReasonTranslator
     public function __construct(
         private readonly ProviderReasonTranslator $providerReasonTranslator,
         private readonly FallbackReasonTranslator $fallbackReasonTranslator,
+        private readonly PlatformVocabularyGlossary $glossary,
     ) {}
 
     /**
@@ -44,7 +46,7 @@ public function translate(
             return null;
         }
 
-        return match (true) {
+        $envelope = match (true) {
             $artifactKey === ProviderReasonTranslator::ARTIFACT_KEY,
             $artifactKey === null && $this->providerReasonTranslator->canTranslate($reasonCode) => $this->providerReasonTranslator->translate($reasonCode, $surface, $context),
             $artifactKey === self::GOVERNANCE_ARTIFACT_TRUTH_ARTIFACT && BaselineCompareReasonCode::tryFrom($reasonCode) instanceof BaselineCompareReasonCode => $this->translateBaselineCompareReason($reasonCode),
@@ -62,6 +64,36 @@ public function translate(
             $artifactKey === null && ProviderReasonCodes::isKnown($reasonCode) => $this->providerReasonTranslator->translate($reasonCode, $surface, $context),
             default => $this->fallbackTranslate($reasonCode, $artifactKey, $surface, $context),
         };
+
+        return $this->withOwnership($envelope, $reasonCode, $artifactKey);
+    }
+
+    /**
+     * @param  array<string, mixed>  $context
+     */
+    public function boundaryClassification(
+        ?string $reasonCode,
+        ?string $artifactKey = null,
+        string $surface = 'detail',
+        array $context = [],
+    ): ?string {
+        return $this->boundaryClassificationForEnvelope(
+            $this->translate($reasonCode, $artifactKey, $surface, $context),
+        );
+    }
+
+    public function boundaryClassificationForEnvelope(?ReasonResolutionEnvelope $envelope): ?string
+    {
+        return $this->boundaryClassificationForNamespace($envelope?->ownerNamespace());
+    }
+
+    public function boundaryClassificationForNamespace(?string $ownerNamespace): ?string
+    {
+        if (! is_string($ownerNamespace) || trim($ownerNamespace) === '') {
+            return null;
+        }
+
+        return $this->glossary->classifyReasonNamespace($ownerNamespace);
     }
 
     /**
@@ -182,6 +214,12 @@ private function translateBaselineReason(string $reasonCode): ReasonResolutionEn
                 'prerequisite_missing',
                 'Refresh the page and select a valid snapshot for this baseline profile.',
             ],
+            BaselineReasonCodes::COMPARE_MIXED_SCOPE => [
+                'Mixed compare scope',
+                'The selected governed subjects span multiple compare strategy families, so TenantPilot will not start one misleading combined compare run.',
+                'prerequisite_missing',
+                'Narrow the governed subject selection so one compare strategy family owns the requested scope.',
+            ],
             default => [
                 'Baseline workflow blocked',
                 'TenantPilot recorded a baseline precondition that prevents this workflow from continuing safely.',
@@ -236,6 +274,24 @@ private function translateBaselineCompareReason(string $reasonCode): ReasonResol
                 'prerequisite_missing',
                 'Resume or rerun evidence capture before relying on this compare result.',
             ],
+            BaselineCompareReasonCode::UnsupportedSubjects => [
+                'Unsupported subjects remained',
+                'The comparison finished, but one or more in-scope subjects are not currently supported by the selected compare strategy.',
+                'prerequisite_missing',
+                'Narrow scope or wait for support before treating zero visible findings as complete.',
+            ],
+            BaselineCompareReasonCode::AmbiguousSubjects => [
+                'Subject identity stayed ambiguous',
+                'The comparison finished, but one or more in-scope subjects could not be matched cleanly enough to produce a trustworthy result.',
+                'prerequisite_missing',
+                'Review the ambiguous subject mapping before relying on this compare result.',
+            ],
+            BaselineCompareReasonCode::StrategyFailed => [
+                'Strategy processing failed',
+                'The comparison finished without a fully usable result because strategy-owned subject processing failed for one or more in-scope subjects.',
+                'retryable_transient',
+                'Inspect the compare run diagnostics and retry once the subject-processing failure is addressed.',
+            ],
             BaselineCompareReasonCode::RolloutDisabled => [
                 'Compare rollout disabled',
                 'The comparison path was limited by rollout configuration, so the result is not decision-grade.',
@@ -248,6 +304,24 @@ private function translateBaselineCompareReason(string $reasonCode): ReasonResol
                 'prerequisite_missing',
                 'Review scope selection and baseline inputs before comparing again.',
             ],
+            BaselineCompareReasonCode::OverdueFindingsRemain => [
+                'Overdue findings remain',
+                'The latest compare did not produce new drift, but overdue findings still require attention.',
+                'prerequisite_missing',
+                'Review and resolve the overdue findings before treating this posture as healthy.',
+            ],
+            BaselineCompareReasonCode::GovernanceExpiring => [
+                'Accepted-risk governance is expiring',
+                'Accepted-risk coverage is still valid, but renewal is approaching and needs review.',
+                'prerequisite_missing',
+                'Review the expiring governance before it lapses.',
+            ],
+            BaselineCompareReasonCode::GovernanceLapsed => [
+                'Accepted-risk governance lapsed',
+                'Accepted-risk coverage has lapsed, so the current posture still needs follow-up.',
+                'prerequisite_missing',
+                'Restore valid governance or move the affected findings back into active remediation.',
+            ],
         };
 
         return new ReasonResolutionEnvelope(
@@ -263,4 +337,101 @@ private function translateBaselineCompareReason(string $reasonCode): ReasonResol
             absencePattern: $enum->absencePattern(),
         );
     }
+
+    private function withOwnership(
+        ?ReasonResolutionEnvelope $envelope,
+        string $reasonCode,
+        ?string $artifactKey,
+    ): ?ReasonResolutionEnvelope {
+        if (! $envelope instanceof ReasonResolutionEnvelope) {
+            return null;
+        }
+
+        if ($envelope->reasonOwnership instanceof ReasonOwnershipDescriptor) {
+            return $envelope;
+        }
+
+        $ownership = match (true) {
+            $artifactKey === ProviderReasonTranslator::ARTIFACT_KEY,
+            $artifactKey === null && ProviderReasonCodes::isKnown($reasonCode) => ProviderReasonCodes::ownershipDescriptor($reasonCode),
+            $artifactKey === self::RBAC_ARTIFACT,
+            $artifactKey === null && RbacReason::tryFrom($reasonCode) instanceof RbacReason => new ReasonOwnershipDescriptor(
+                ownerLayer: 'domain_owned',
+                ownerNamespace: 'rbac.intune',
+                reasonCode: $reasonCode,
+                platformReasonFamily: PlatformReasonFamily::Authorization,
+            ),
+            $artifactKey === self::TENANT_OPERABILITY_ARTIFACT,
+            $artifactKey === null && TenantOperabilityReasonCode::tryFrom($reasonCode) instanceof TenantOperabilityReasonCode => new ReasonOwnershipDescriptor(
+                ownerLayer: 'platform_core',
+                ownerNamespace: 'tenant_operability',
+                reasonCode: $reasonCode,
+                platformReasonFamily: PlatformReasonFamily::Availability,
+            ),
+            $artifactKey === self::EXECUTION_DENIAL_ARTIFACT,
+            $artifactKey === null && ExecutionDenialReasonCode::tryFrom($reasonCode) instanceof ExecutionDenialReasonCode => new ReasonOwnershipDescriptor(
+                ownerLayer: 'platform_core',
+                ownerNamespace: 'execution_denial',
+                reasonCode: $reasonCode,
+                platformReasonFamily: PlatformReasonFamily::Authorization,
+            ),
+            $artifactKey === null && LifecycleReconciliationReason::tryFrom($reasonCode) instanceof LifecycleReconciliationReason => new ReasonOwnershipDescriptor(
+                ownerLayer: 'platform_core',
+                ownerNamespace: 'operation_lifecycle',
+                reasonCode: $reasonCode,
+                platformReasonFamily: PlatformReasonFamily::Execution,
+            ),
+            $artifactKey === self::GOVERNANCE_ARTIFACT_TRUTH_ARTIFACT && BaselineCompareReasonCode::tryFrom($reasonCode) instanceof BaselineCompareReasonCode,
+            $artifactKey === null && BaselineCompareReasonCode::tryFrom($reasonCode) instanceof BaselineCompareReasonCode => new ReasonOwnershipDescriptor(
+                ownerLayer: 'domain_owned',
+                ownerNamespace: 'governance.baseline_compare',
+                reasonCode: $reasonCode,
+                platformReasonFamily: $this->baselineCompareFamily($reasonCode),
+            ),
+            $artifactKey === self::GOVERNANCE_ARTIFACT_TRUTH_ARTIFACT && BaselineReasonCodes::isKnown($reasonCode),
+            $artifactKey === null && BaselineReasonCodes::isKnown($reasonCode) => new ReasonOwnershipDescriptor(
+                ownerLayer: 'domain_owned',
+                ownerNamespace: 'governance.artifact_truth',
+                reasonCode: $reasonCode,
+                platformReasonFamily: $this->baselineReasonFamily($reasonCode),
+            ),
+            default => new ReasonOwnershipDescriptor(
+                ownerLayer: 'platform_core',
+                ownerNamespace: 'reason_translation.fallback',
+                reasonCode: $reasonCode,
+                platformReasonFamily: PlatformReasonFamily::Compatibility,
+            ),
+        };
+
+        return $envelope->withReasonOwnership($ownership);
+    }
+
+    private function baselineCompareFamily(string $reasonCode): PlatformReasonFamily
+    {
+        return match (BaselineCompareReasonCode::tryFrom($reasonCode)) {
+            BaselineCompareReasonCode::CoverageUnproven,
+            BaselineCompareReasonCode::EvidenceCaptureIncomplete,
+            BaselineCompareReasonCode::UnsupportedSubjects,
+            BaselineCompareReasonCode::AmbiguousSubjects,
+            BaselineCompareReasonCode::NoSubjectsInScope,
+            BaselineCompareReasonCode::NoDriftDetected => PlatformReasonFamily::Coverage,
+            BaselineCompareReasonCode::StrategyFailed => PlatformReasonFamily::Execution,
+            BaselineCompareReasonCode::RolloutDisabled => PlatformReasonFamily::Compatibility,
+            BaselineCompareReasonCode::OverdueFindingsRemain,
+            BaselineCompareReasonCode::GovernanceExpiring,
+            BaselineCompareReasonCode::GovernanceLapsed => PlatformReasonFamily::Prerequisite,
+            default => PlatformReasonFamily::Compatibility,
+        };
+    }
+
+    private function baselineReasonFamily(string $reasonCode): PlatformReasonFamily
+    {
+        return match ($reasonCode) {
+            BaselineReasonCodes::COMPARE_MIXED_SCOPE,
+            BaselineReasonCodes::CAPTURE_ROLLOUT_DISABLED,
+            BaselineReasonCodes::COMPARE_ROLLOUT_DISABLED => PlatformReasonFamily::Compatibility,
+            BaselineReasonCodes::SNAPSHOT_CAPTURE_FAILED => PlatformReasonFamily::Execution,
+            default => PlatformReasonFamily::Prerequisite,
+        };
+    }
 }

apps/platform/app/Support/Tenants/TenantOperabilityReasonCode.php

@@ -4,7 +4,10 @@
 
 namespace App\Support\Tenants;
 
+use App\Support\Governance\PlatformVocabularyGlossary;
 use App\Support\ReasonTranslation\NextStepOption;
+use App\Support\ReasonTranslation\PlatformReasonFamily;
+use App\Support\ReasonTranslation\ReasonOwnershipDescriptor;
 use App\Support\ReasonTranslation\ReasonResolutionEnvelope;
 
 enum TenantOperabilityReasonCode: string
@@ -61,6 +64,26 @@ public function actionability(): string
         };
     }
 
+    public function ownerLayer(): string
+    {
+        return PlatformVocabularyGlossary::OWNER_PLATFORM_CORE;
+    }
+
+    public function ownerNamespace(): string
+    {
+        return 'tenant_operability';
+    }
+
+    public function platformReasonFamily(): PlatformReasonFamily
+    {
+        return PlatformReasonFamily::Availability;
+    }
+
+    public function boundaryClassification(): string
+    {
+        return PlatformVocabularyGlossary::BOUNDARY_PLATFORM_CORE;
+    }
+
     /**
      * @return array<int, NextStepOption>
      */
@@ -102,6 +125,12 @@ public function toReasonResolutionEnvelope(string $surface = 'detail', array $co
             nextSteps: $this->nextSteps(),
             showNoActionNeeded: $this->actionability() === 'non_actionable',
             diagnosticCodeLabel: $this->value,
+            reasonOwnership: new ReasonOwnershipDescriptor(
+                ownerLayer: $this->ownerLayer(),
+                ownerNamespace: $this->ownerNamespace(),
+                reasonCode: $this->value,
+                platformReasonFamily: $this->platformReasonFamily(),
+            ),
         );
     }
 }

apps/platform/app/Support/Ui/GovernanceArtifactTruth/ArtifactTruthCause.php

@@ -5,6 +5,8 @@
 namespace App\Support\Ui\GovernanceArtifactTruth;
 
 use App\Support\ReasonTranslation\NextStepOption;
+use App\Support\ReasonTranslation\PlatformReasonFamily;
+use App\Support\ReasonTranslation\ReasonOwnershipDescriptor;
 use App\Support\ReasonTranslation\ReasonResolutionEnvelope;
 use App\Support\Ui\OperatorExplanation\TrustworthinessLevel;
 
@@ -22,6 +24,9 @@ public function __construct(
         public string $trustImpact,
         public ?string $absencePattern,
         public array $nextSteps = [],
+        public ?string $ownerLayer = null,
+        public ?string $ownerNamespace = null,
+        public ?string $platformReasonFamily = null,
     ) {}
 
     public static function fromReasonResolutionEnvelope(
@@ -44,11 +49,32 @@ public static function fromReasonResolutionEnvelope(
                 static fn (NextStepOption $nextStep): string => $nextStep->label,
                 $reason->nextSteps,
             )),
+            ownerLayer: $reason->ownerLayer(),
+            ownerNamespace: $reason->ownerNamespace(),
+            platformReasonFamily: $reason->platformReasonFamily(),
         );
     }
 
     public function toReasonResolutionEnvelope(): ReasonResolutionEnvelope
     {
+        $reasonOwnership = null;
+        $family = is_string($this->platformReasonFamily)
+            ? PlatformReasonFamily::tryFrom($this->platformReasonFamily)
+            : null;
+
+        if (is_string($this->ownerLayer)
+            && trim($this->ownerLayer) !== ''
+            && is_string($this->ownerNamespace)
+            && trim($this->ownerNamespace) !== ''
+            && $family instanceof PlatformReasonFamily) {
+            $reasonOwnership = new ReasonOwnershipDescriptor(
+                ownerLayer: trim($this->ownerLayer),
+                ownerNamespace: trim($this->ownerNamespace),
+                reasonCode: $this->reasonCode ?? 'artifact_truth_reason',
+                platformReasonFamily: $family,
+            );
+        }
+
         return new ReasonResolutionEnvelope(
             internalCode: $this->reasonCode ?? 'artifact_truth_reason',
             operatorLabel: $this->operatorLabel ?? 'Operator attention required',
@@ -61,6 +87,7 @@ public function toReasonResolutionEnvelope(): ReasonResolutionEnvelope
             diagnosticCodeLabel: $this->diagnosticCode,
             trustImpact: $this->trustImpact !== '' ? $this->trustImpact : TrustworthinessLevel::LimitedConfidence->value,
             absencePattern: $this->absencePattern,
+            reasonOwnership: $reasonOwnership,
         );
     }
 
@@ -73,7 +100,10 @@ public function toReasonResolutionEnvelope(): ReasonResolutionEnvelope
      *     diagnosticCode: ?string,
      *     trustImpact: string,
      *     absencePattern: ?string,
-     *     nextSteps: array<int, string>
+     *     nextSteps: array<int, string>,
+     *     ownerLayer: ?string,
+     *     ownerNamespace: ?string,
+     *     platformReasonFamily: ?string
      * }
      */
     public function toArray(): array
@@ -87,6 +117,9 @@ public function toArray(): array
             'trustImpact' => $this->trustImpact,
             'absencePattern' => $this->absencePattern,
             'nextSteps' => $this->nextSteps,
+            'ownerLayer' => $this->ownerLayer,
+            'ownerNamespace' => $this->ownerNamespace,
+            'platformReasonFamily' => $this->platformReasonFamily,
         ];
     }
 }

apps/platform/config/tenantpilot.php

@@ -597,6 +597,248 @@
         ],
     ],
 
+    'platform_vocabulary' => [
+        'terms' => [
+            'governed_subject' => [
+                'term_key' => 'governed_subject',
+                'canonical_label' => 'Governed subject',
+                'canonical_description' => 'The platform-facing noun for a governed object across compare, snapshot, evidence, and review surfaces.',
+                'boundary_classification' => 'platform_core',
+                'owner_layer' => 'platform_core',
+                'allowed_contexts' => ['compare', 'snapshot', 'evidence', 'review', 'reporting'],
+                'legacy_aliases' => ['policy_type'],
+                'alias_retirement_path' => 'Retire false-universal policy_type wording from platform-owned summaries and descriptors while preserving Intune-owned storage.',
+                'forbidden_platform_aliases' => ['policy_type'],
+            ],
+            'domain_key' => [
+                'term_key' => 'domain_key',
+                'canonical_label' => 'Governance domain',
+                'canonical_description' => 'The canonical domain discriminator for cross-domain and platform-near contracts.',
+                'boundary_classification' => 'cross_domain_governance',
+                'owner_layer' => 'platform_core',
+                'allowed_contexts' => ['governance', 'compare', 'snapshot', 'reporting'],
+                'legacy_aliases' => [],
+                'alias_retirement_path' => null,
+                'forbidden_platform_aliases' => [],
+            ],
+            'subject_class' => [
+                'term_key' => 'subject_class',
+                'canonical_label' => 'Subject class',
+                'canonical_description' => 'The canonical subject-class discriminator for governed-subject contracts.',
+                'boundary_classification' => 'cross_domain_governance',
+                'owner_layer' => 'platform_core',
+                'allowed_contexts' => ['governance', 'compare', 'snapshot'],
+                'legacy_aliases' => [],
+                'alias_retirement_path' => null,
+                'forbidden_platform_aliases' => [],
+            ],
+            'subject_type_key' => [
+                'term_key' => 'subject_type_key',
+                'canonical_label' => 'Governed subject key',
+                'canonical_description' => 'The domain-owned subject-family key used by platform-near descriptors.',
+                'boundary_classification' => 'cross_domain_governance',
+                'owner_layer' => 'platform_core',
+                'allowed_contexts' => ['governance', 'compare', 'snapshot', 'evidence'],
+                'legacy_aliases' => ['policy_type'],
+                'alias_retirement_path' => 'Prefer subject_type_key on platform-near payloads and keep policy_type only where the owning model is Intune-specific.',
+                'forbidden_platform_aliases' => ['policy_type'],
+            ],
+            'subject_type_label' => [
+                'term_key' => 'subject_type_label',
+                'canonical_label' => 'Governed subject label',
+                'canonical_description' => 'The operator-facing label for a governed subject family.',
+                'boundary_classification' => 'cross_domain_governance',
+                'owner_layer' => 'platform_core',
+                'allowed_contexts' => ['snapshot', 'evidence', 'compare', 'review'],
+                'legacy_aliases' => [],
+                'alias_retirement_path' => null,
+                'forbidden_platform_aliases' => [],
+            ],
+            'resource_type' => [
+                'term_key' => 'resource_type',
+                'canonical_label' => 'Resource type',
+                'canonical_description' => 'Optional resource-shaped noun for platform-facing summaries when a governed subject also needs a resource family label.',
+                'boundary_classification' => 'platform_core',
+                'owner_layer' => 'platform_core',
+                'allowed_contexts' => ['reporting', 'review'],
+                'legacy_aliases' => [],
+                'alias_retirement_path' => null,
+                'forbidden_platform_aliases' => [],
+            ],
+            'operation_type' => [
+                'term_key' => 'operation_type',
+                'canonical_label' => 'Operation type',
+                'canonical_description' => 'The canonical platform operation identifier shown on monitoring and launch surfaces.',
+                'boundary_classification' => 'platform_core',
+                'owner_layer' => 'platform_core',
+                'allowed_contexts' => ['monitoring', 'reporting', 'launch_surfaces'],
+                'legacy_aliases' => ['type'],
+                'alias_retirement_path' => 'Expose canonical operation_type on read models while operation_runs.type remains a compatibility storage seam during rollout.',
+                'forbidden_platform_aliases' => [],
+            ],
+            'platform_reason_family' => [
+                'term_key' => 'platform_reason_family',
+                'canonical_label' => 'Platform reason family',
+                'canonical_description' => 'The cross-domain platform family that explains the top-level cause category without erasing domain ownership.',
+                'boundary_classification' => 'platform_core',
+                'owner_layer' => 'platform_core',
+                'allowed_contexts' => ['reason_translation', 'monitoring', 'review', 'reporting'],
+                'legacy_aliases' => [],
+                'alias_retirement_path' => null,
+                'forbidden_platform_aliases' => [],
+            ],
+            'reason_owner.owner_namespace' => [
+                'term_key' => 'reason_owner.owner_namespace',
+                'canonical_label' => 'Reason owner namespace',
+                'canonical_description' => 'The explicit namespace that marks whether a translated reason is provider-owned, governance-owned, access-owned, or runtime-owned.',
+                'boundary_classification' => 'platform_core',
+                'owner_layer' => 'platform_core',
+                'allowed_contexts' => ['reason_translation', 'review', 'reporting'],
+                'legacy_aliases' => [],
+                'alias_retirement_path' => null,
+                'forbidden_platform_aliases' => [],
+            ],
+            'reason_code' => [
+                'term_key' => 'reason_code',
+                'canonical_label' => 'Reason code',
+                'canonical_description' => 'The original domain-owned or provider-owned reason identifier preserved for diagnostics and translation lookup.',
+                'boundary_classification' => 'platform_core',
+                'owner_layer' => 'platform_core',
+                'allowed_contexts' => ['reason_translation', 'diagnostics'],
+                'legacy_aliases' => [],
+                'alias_retirement_path' => null,
+                'forbidden_platform_aliases' => [],
+            ],
+            'registry_key' => [
+                'term_key' => 'registry_key',
+                'canonical_label' => 'Registry key',
+                'canonical_description' => 'The stable identifier for a contributor-facing registry or catalog.',
+                'boundary_classification' => 'platform_core',
+                'owner_layer' => 'platform_core',
+                'allowed_contexts' => ['governance', 'contributor_guidance'],
+                'legacy_aliases' => [],
+                'alias_retirement_path' => null,
+                'forbidden_platform_aliases' => [],
+            ],
+            'boundary_classification' => [
+                'term_key' => 'boundary_classification',
+                'canonical_label' => 'Boundary classification',
+                'canonical_description' => 'The explicit classification that marks a term or registry as platform_core, cross_domain_governance, or intune_specific.',
+                'boundary_classification' => 'platform_core',
+                'owner_layer' => 'platform_core',
+                'allowed_contexts' => ['governance', 'contributor_guidance'],
+                'legacy_aliases' => [],
+                'alias_retirement_path' => null,
+                'forbidden_platform_aliases' => [],
+            ],
+            'policy_type' => [
+                'term_key' => 'policy_type',
+                'canonical_label' => 'Intune policy type',
+                'canonical_description' => 'The Intune-specific discriminator that remains valid on adapter-owned or Intune-owned models but must not be treated as a universal platform noun.',
+                'boundary_classification' => 'intune_specific',
+                'owner_layer' => 'domain_owned',
+                'allowed_contexts' => ['intune_adapter', 'intune_inventory', 'intune_backup'],
+                'legacy_aliases' => [],
+                'alias_retirement_path' => null,
+                'forbidden_platform_aliases' => ['governed_subject'],
+            ],
+        ],
+        'reason_namespaces' => [
+            'tenant_operability' => [
+                'owner_namespace' => 'tenant_operability',
+                'boundary_classification' => 'platform_core',
+                'owner_layer' => 'platform_core',
+                'compatibility_notes' => 'Tenant operability reasons are platform-core guardrails for workspace and tenant context.',
+            ],
+            'execution_denial' => [
+                'owner_namespace' => 'execution_denial',
+                'boundary_classification' => 'platform_core',
+                'owner_layer' => 'platform_core',
+                'compatibility_notes' => 'Execution denial reasons remain platform-core run-legitimacy semantics.',
+            ],
+            'operation_lifecycle' => [
+                'owner_namespace' => 'operation_lifecycle',
+                'boundary_classification' => 'platform_core',
+                'owner_layer' => 'platform_core',
+                'compatibility_notes' => 'Lifecycle reconciliation reasons remain platform-core monitoring semantics.',
+            ],
+            'governance.baseline_compare' => [
+                'owner_namespace' => 'governance.baseline_compare',
+                'boundary_classification' => 'cross_domain_governance',
+                'owner_layer' => 'domain_owned',
+                'compatibility_notes' => 'Baseline-compare reason codes are governance-owned details translated through the platform boundary.',
+            ],
+            'governance.artifact_truth' => [
+                'owner_namespace' => 'governance.artifact_truth',
+                'boundary_classification' => 'cross_domain_governance',
+                'owner_layer' => 'domain_owned',
+                'compatibility_notes' => 'Artifact-truth reason codes remain governance-owned and are surfaced through platform-safe summaries.',
+            ],
+            'provider.microsoft_graph' => [
+                'owner_namespace' => 'provider.microsoft_graph',
+                'boundary_classification' => 'intune_specific',
+                'owner_layer' => 'provider_owned',
+                'compatibility_notes' => 'Microsoft Graph provider reasons remain provider-owned and Intune-specific.',
+            ],
+            'provider.intune_rbac' => [
+                'owner_namespace' => 'provider.intune_rbac',
+                'boundary_classification' => 'intune_specific',
+                'owner_layer' => 'provider_owned',
+                'compatibility_notes' => 'Provider-owned Intune RBAC reasons remain Intune-specific.',
+            ],
+            'rbac.intune' => [
+                'owner_namespace' => 'rbac.intune',
+                'boundary_classification' => 'intune_specific',
+                'owner_layer' => 'domain_owned',
+                'compatibility_notes' => 'RBAC detail remains Intune-specific domain context.',
+            ],
+            'reason_translation.fallback' => [
+                'owner_namespace' => 'reason_translation.fallback',
+                'boundary_classification' => 'platform_core',
+                'owner_layer' => 'platform_core',
+                'compatibility_notes' => 'Fallback translation remains a platform-core compatibility seam until a domain owner is known.',
+            ],
+        ],
+        'registries' => [
+            'governance_subject_taxonomy_registry' => [
+                'registry_key' => 'governance_subject_taxonomy_registry',
+                'boundary_classification' => 'cross_domain_governance',
+                'owner_layer' => 'platform_core',
+                'source_class_or_file' => App\Support\Governance\GovernanceSubjectTaxonomyRegistry::class,
+                'canonical_nouns' => ['domain_key', 'subject_class', 'subject_type_key', 'subject_type_label'],
+                'allowed_consumers' => ['baseline_scope', 'compare', 'snapshot', 'review'],
+                'compatibility_notes' => 'Provides the governed-subject source of truth, resolves legacy policy-type payloads, and preserves inactive or future-domain entries without exposing them as active operator choices.',
+            ],
+            'operation_catalog' => [
+                'registry_key' => 'operation_catalog',
+                'boundary_classification' => 'platform_core',
+                'owner_layer' => 'platform_core',
+                'source_class_or_file' => App\Support\OperationCatalog::class,
+                'canonical_nouns' => ['operation_type'],
+                'allowed_consumers' => ['monitoring', 'reporting', 'launch_surfaces', 'audit'],
+                'compatibility_notes' => 'Resolves canonical operation meaning from historical storage values without treating every stored raw string as equally canonical.',
+            ],
+            'provider_reason_codes' => [
+                'registry_key' => 'provider_reason_codes',
+                'boundary_classification' => 'intune_specific',
+                'owner_layer' => 'provider_owned',
+                'source_class_or_file' => App\Support\Providers\ProviderReasonCodes::class,
+                'canonical_nouns' => ['reason_code'],
+                'allowed_consumers' => ['reason_translation'],
+                'compatibility_notes' => 'Provider-owned reason codes remain namespaced domain details and become platform-safe only through the reason-translation boundary.',
+            ],
+            'inventory_policy_type_catalog' => [
+                'registry_key' => 'inventory_policy_type_catalog',
+                'boundary_classification' => 'intune_specific',
+                'owner_layer' => 'domain_owned',
+                'source_class_or_file' => App\Support\Inventory\InventoryPolicyTypeMeta::class,
+                'canonical_nouns' => ['policy_type'],
+                'allowed_consumers' => ['intune_adapter', 'inventory', 'backup'],
+                'compatibility_notes' => 'The supported Intune policy-type list is not a universal platform registry and must be wrapped before reuse on platform-near summaries.',
+            ],
+        ],
+    ],
+
     'hardening' => [
         'intune_write_gate' => [
             'enabled' => (bool) env('TENANTPILOT_INTUNE_WRITE_GATE_ENABLED', true),

apps/platform/lang/en/baseline-compare.php

@@ -30,10 +30,10 @@
     'badge_evidence_gaps' => 'Evidence gaps: :count',
     'evidence_gaps_tooltip' => 'Top gaps: :summary',
     'evidence_gap_details_heading' => 'Evidence gap details',
-    'evidence_gap_details_description' => 'Search recorded gap subjects by reason, policy type, subject class, outcome, next action, or subject key before falling back to raw diagnostics.',
+    'evidence_gap_details_description' => 'Search recorded gap subjects by reason, governed subject, subject class, outcome, next action, or subject key before falling back to raw diagnostics.',
     'evidence_gap_search_label' => 'Search gap details',
     'evidence_gap_search_placeholder' => 'Search by reason, type, class, outcome, action, or subject key',
-    'evidence_gap_search_help' => 'Filter matches across reason, policy type, subject class, outcome, next action, and subject key.',
+    'evidence_gap_search_help' => 'Filter matches across reason, governed subject, subject class, outcome, next action, and subject key.',
     'evidence_gap_bucket_help_ambiguous_match' => 'Multiple inventory records matched the same policy subject — inspect the mapping to confirm the correct pairing.',
     'evidence_gap_bucket_help_policy_record_missing' => 'The expected policy record was not found in the baseline snapshot — verify the policy still exists in the tenant.',
     'evidence_gap_bucket_help_inventory_record_missing' => 'No inventory record could be matched for these subjects — confirm the inventory sync is current.',
@@ -57,7 +57,7 @@
     'evidence_gap_legacy_body' => 'This run still uses the retired broad reason shape. Regenerate the run or purge stale local development payloads before treating the gap details as operator-safe.',
     'evidence_gap_diagnostics_heading' => 'Baseline compare evidence',
     'evidence_gap_diagnostics_description' => 'Raw diagnostics remain available for support and deep troubleshooting after the operator summary and searchable detail.',
-    'evidence_gap_policy_type' => 'Policy type',
+    'evidence_gap_policy_type' => 'Governed subject',
     'evidence_gap_subject_class' => 'Subject class',
     'evidence_gap_outcome' => 'Outcome',
     'evidence_gap_next_action' => 'Next action',

apps/platform/resources/views/filament/infolists/entries/baseline-snapshot-groups.blade.php

@@ -33,7 +33,7 @@
             @endphp
 
             <x-filament::section
-                :heading="$group['label'] ?? ($group['policyType'] ?? 'Policy type')"
+                :heading="$group['subjectDescriptor']['display_label'] ?? ($group['label'] ?? ($group['policyType'] ?? 'Governed subject'))"
                 :description="$group['coverageHint'] ?? null"
                 collapsible
                 :collapsed="(bool) ($group['initiallyCollapsed'] ?? true)"
@@ -84,7 +84,7 @@
                                             {{ $item['label'] ?? 'Snapshot item' }}
                                         </div>
                                         <div class="text-xs text-gray-500 dark:text-gray-400">
-                                            {{ $item['typeLabel'] ?? 'Policy type' }}
+                                            {{ $item['typeLabel'] ?? 'Governed subject family' }}
                                         </div>
                                     </div>
 

apps/platform/resources/views/filament/infolists/entries/baseline-snapshot-summary-table.blade.php

@@ -22,14 +22,14 @@
 <div class="space-y-3">
     @if ($rows === [])
         <div class="rounded-lg border border-dashed border-gray-300 px-4 py-6 text-sm text-gray-600 dark:border-gray-700 dark:text-gray-300">
-            No captured policy types are available in this snapshot.
+            No captured governed subjects are available in this snapshot.
         </div>
     @else
         <div class="overflow-x-auto rounded-lg border border-gray-200 dark:border-gray-700">
             <table class="min-w-full divide-y divide-gray-200 text-left text-sm dark:divide-gray-700">
                 <thead class="bg-gray-50 dark:bg-gray-900/50">
                     <tr class="text-xs uppercase tracking-wide text-gray-500 dark:text-gray-400">
-                        <th class="px-4 py-3">Policy type</th>
+                        <th class="px-4 py-3">Governed subject</th>
                         <th class="px-4 py-3">Items</th>
                         <th class="px-4 py-3">Fidelity</th>
                         <th class="px-4 py-3">Coverage state</th>
@@ -47,7 +47,7 @@
 
                         <tr class="align-top">
                             <td class="px-4 py-3 font-medium text-gray-900 dark:text-white">
-                                {{ $row['label'] ?? ($row['policyType'] ?? 'Policy type') }}
+                                {{ $row['governedSubjectLabel'] ?? ($row['label'] ?? ($row['policyType'] ?? 'Governed subject')) }}
                             </td>
                             <td class="px-4 py-3 text-gray-700 dark:text-gray-200">
                                 {{ (int) ($row['itemCount'] ?? 0) }}

apps/platform/resources/views/filament/infolists/entries/baseline-snapshot-technical-detail.blade.php

@@ -17,7 +17,7 @@
         <div class="space-y-3">
             @foreach ($groupPayloads as $group)
                 @php
-                    $label = $group['label'] ?? 'Policy type';
+                    $label = $group['payload']['subject_descriptor']['display_label'] ?? ($group['label'] ?? 'Governed subject');
                     $payload = is_array($group['payload'] ?? null) ? $group['payload'] : [];
                 @endphp
 

apps/platform/resources/views/filament/infolists/entries/tenant-review-summary.blade.php

@@ -8,6 +8,7 @@
     $contextLinks = is_array($state['context_links'] ?? null) ? $state['context_links'] : [];
     $publishBlockers = is_array($state['publish_blockers'] ?? null) ? $state['publish_blockers'] : [];
     $operatorExplanation = is_array($state['operator_explanation'] ?? null) ? $state['operator_explanation'] : [];
+    $reasonSemantics = is_array($state['reason_semantics'] ?? null) ? $state['reason_semantics'] : [];
 @endphp
 
 <div class="space-y-4">
@@ -31,6 +32,20 @@
         </div>
     @endif
 
+    @if ($reasonSemantics !== [])
+        <dl class="grid grid-cols-1 gap-3 md:grid-cols-2">
+            <div class="rounded-md border border-gray-100 bg-gray-50 px-3 py-2 dark:border-gray-800 dark:bg-gray-950/60">
+                <dt class="text-[11px] font-semibold uppercase tracking-wide text-gray-500 dark:text-gray-400">Reason owner</dt>
+                <dd class="mt-1 text-sm text-gray-900 dark:text-gray-100">{{ $reasonSemantics['owner_label'] ?? 'Platform core' }}</dd>
+            </div>
+
+            <div class="rounded-md border border-gray-100 bg-gray-50 px-3 py-2 dark:border-gray-800 dark:bg-gray-950/60">
+                <dt class="text-[11px] font-semibold uppercase tracking-wide text-gray-500 dark:text-gray-400">Platform reason family</dt>
+                <dd class="mt-1 text-sm text-gray-900 dark:text-gray-100">{{ $reasonSemantics['family_label'] ?? 'Compatibility' }}</dd>
+            </div>
+        </dl>
+    @endif
+
     <dl class="grid grid-cols-2 gap-3 xl:grid-cols-4">
         @foreach ($metrics as $metric)
             @php

apps/platform/resources/views/filament/pages/baseline-compare-landing.blade.php

@@ -8,6 +8,7 @@
         $duplicateNamePoliciesCountValue = (int) ($duplicateNamePoliciesCount ?? 0);
         $duplicateNameSubjectsCountValue = (int) ($duplicateNameSubjectsCount ?? 0);
         $explanation = is_array($operatorExplanation ?? null) ? $operatorExplanation : null;
+        $reasonSemantics = is_array($reasonSemantics ?? null) ? $reasonSemantics : null;
         $summary = is_array($summaryAssessment ?? null) ? $summaryAssessment : null;
         $matrixNavigationContext = is_array($navigationContext ?? null) ? $navigationContext : null;
         $arrivedFromCompareMatrix = str_starts_with((string) ($matrixNavigationContext['source_surface'] ?? ''), 'baseline_compare_matrix');
@@ -117,6 +118,24 @@
                     @endif
                 </div>
 
+                @if ($reasonSemantics !== null)
+                    <dl class="grid gap-3 md:grid-cols-2">
+                        <div class="rounded-lg border border-gray-200 bg-gray-50 px-4 py-3 dark:border-gray-800 dark:bg-gray-950/50">
+                            <dt class="text-[11px] font-semibold uppercase tracking-wide text-gray-500 dark:text-gray-400">Reason owner</dt>
+                            <dd class="mt-1 text-sm font-medium text-gray-900 dark:text-white">
+                                {{ $reasonSemantics['owner_label'] ?? 'Platform core' }}
+                            </dd>
+                        </div>
+
+                        <div class="rounded-lg border border-gray-200 bg-gray-50 px-4 py-3 dark:border-gray-800 dark:bg-gray-950/50">
+                            <dt class="text-[11px] font-semibold uppercase tracking-wide text-gray-500 dark:text-gray-400">Platform reason family</dt>
+                            <dd class="mt-1 text-sm font-medium text-gray-900 dark:text-white">
+                                {{ $reasonSemantics['family_label'] ?? 'Compatibility' }}
+                            </dd>
+                        </div>
+                    </dl>
+                @endif
+
                 <dl class="grid gap-3 md:grid-cols-2 xl:grid-cols-4">
                     <div class="rounded-lg border border-gray-200 bg-gray-50 px-4 py-3 dark:border-gray-800 dark:bg-gray-950/50">
                         <dt class="text-[11px] font-semibold uppercase tracking-wide text-gray-500 dark:text-gray-400">Execution outcome</dt>

apps/platform/resources/views/filament/pages/baseline-compare-matrix.blade.php

@@ -340,7 +340,7 @@
                     @if ($policyTypeOptions !== [])
                         <div class="mt-3 flex flex-wrap gap-2">
                             <x-filament::badge color="gray" size="sm">
-                                {{ count($policyTypeOptions) }} searchable policy types
+                                {{ count($policyTypeOptions) }} searchable governed subjects
                             </x-filament::badge>
                             @if ($hiddenAssignedTenantCount > 0)
                                 <x-filament::badge color="gray" size="sm">
@@ -507,7 +507,7 @@
                                             {{ $result['displayName'] ?? $result['subjectKey'] ?? 'Subject' }}
                                         </div>
                                         <div class="text-sm text-gray-500 dark:text-gray-400">
-                                            {{ $result['policyType'] ?? 'Unknown policy type' }}
+                                            {{ $result['governedSubjectLabel'] ?? ($result['policyType'] ?? 'Unknown governed subject') }}
                                         </div>
                                         @if (filled($result['baselineExternalId'] ?? null))
                                             <div class="text-xs text-gray-500 dark:text-gray-400">
@@ -715,7 +715,7 @@
                                                         {{ $subject['displayName'] ?? $subject['subjectKey'] ?? 'Subject' }}
                                                     </div>
                                                     <div class="text-xs text-gray-500 dark:text-gray-400">
-                                                        {{ $subject['policyType'] ?? 'Unknown policy type' }}
+                                                        {{ $subject['governedSubjectLabel'] ?? ($subject['policyType'] ?? 'Unknown governed subject') }}
                                                     </div>
                                                     @if (filled($subject['baselineExternalId'] ?? null))
                                                         <div class="text-xs text-gray-500 dark:text-gray-400">

apps/platform/resources/views/filament/widgets/tenant/tenant-review-pack-card.blade.php

@@ -11,6 +11,8 @@
     /** @var bool $canManage */
     /** @var ?string $downloadUrl */
     /** @var ?string $failedReason */
+    /** @var ?string $failedReasonDetail */
+    /** @var ?array<string, mixed> $failedReasonSemantics */
     /** @var ?string $reviewUrl */
 
     $badgeSpec = $statusEnum ? BadgeCatalog::spec(BadgeDomain::ReviewPackStatus, $statusEnum->value) : null;
@@ -133,11 +135,25 @@
                 </div>
 
                 @if ($failedReason)
-                    <div class="text-sm text-danger-600 dark:text-danger-400">
+                    <div class="text-sm font-medium text-danger-600 dark:text-danger-400">
                         {{ $failedReason }}
                     </div>
                 @endif
 
+                @if ($failedReasonDetail)
+                    <div class="text-xs text-gray-500 dark:text-gray-400">
+                        {{ $failedReasonDetail }}
+                    </div>
+                @endif
+
+                @if (is_array($failedReasonSemantics ?? null))
+                    <div class="text-xs text-gray-500 dark:text-gray-400">
+                        Reason owner: {{ $failedReasonSemantics['owner_label'] ?? 'Platform core' }}
+                        &middot;
+                        Platform reason family: {{ $failedReasonSemantics['family_label'] ?? 'Compatibility' }}
+                    </div>
+                @endif
+
                 <div class="text-xs text-gray-400 dark:text-gray-500">
                     {{ $pack->updated_at?->diffForHumans() ?? '—' }}
                 </div>

apps/platform/tests/Architecture/PlatformVocabularyBoundaryGuardTest.php

@@ -0,0 +1,28 @@
+<?php
+
+declare(strict_types=1);
+
+use App\Support\Governance\PlatformVocabularyGlossary;
+use App\Support\OperationCatalog;
+
+it('keeps touched registry ownership metadata inside the allowed three-way boundary classification', function (): void {
+    $classifications = collect(app(PlatformVocabularyGlossary::class)->registries())
+        ->map(static fn ($descriptor): string => $descriptor->boundaryClassification)
+        ->unique()
+        ->values()
+        ->all();
+
+    expect($classifications)->toEqualCanonicalizing([
+        PlatformVocabularyGlossary::BOUNDARY_CROSS_DOMAIN_GOVERNANCE,
+        PlatformVocabularyGlossary::BOUNDARY_PLATFORM_CORE,
+        PlatformVocabularyGlossary::BOUNDARY_INTUNE_SPECIFIC,
+    ]);
+});
+
+it('guards the false-universal policy_type alias behind explicit context-aware vocabulary helpers', function (): void {
+    $glossary = app(PlatformVocabularyGlossary::class);
+
+    expect($glossary->term('policy_type')?->boundaryClassification)->toBe(PlatformVocabularyGlossary::BOUNDARY_INTUNE_SPECIFIC)
+        ->and($glossary->resolveAlias('policy_type', 'compare')?->termKey)->toBe('governed_subject')
+        ->and(OperationCatalog::canonicalCode('baseline_capture'))->toBe('baseline.capture');
+});

apps/platform/tests/Architecture/ReasonTranslationPrimarySurfaceGuardTest.php

@@ -2,6 +2,8 @@
 
 declare(strict_types=1);
 
+use App\Support\Baselines\BaselineCompareReasonCode;
+use App\Support\Governance\PlatformVocabularyGlossary;
 use App\Support\Operations\ExecutionDenialReasonCode;
 use App\Support\Providers\ProviderReasonCodes;
 use App\Support\RbacReason;
@@ -32,3 +34,24 @@
         ->and(TenantOperabilityReasonCode::TenantAlreadyArchived->toReasonResolutionEnvelope()->guidanceText())->toBe('No action needed.')
         ->and(RbacReason::ManualAssignmentRequired->toReasonResolutionEnvelope()->operatorLabel)->toBe('Manual role assignment required');
 });
+
+it('keeps primary-surface reason ownership inside the allowed three-way boundary classification', function (): void {
+    $translator = app(ReasonTranslator::class);
+    $classifications = collect([
+        $translator->boundaryClassification(ExecutionDenialReasonCode::MissingCapability->value, ReasonTranslator::EXECUTION_DENIAL_ARTIFACT),
+        $translator->boundaryClassification(ProviderReasonCodes::ProviderConsentMissing),
+        $translator->boundaryClassification(TenantOperabilityReasonCode::RememberedContextStale->value, ReasonTranslator::TENANT_OPERABILITY_ARTIFACT),
+        $translator->boundaryClassification(RbacReason::ManualAssignmentRequired->value, ReasonTranslator::RBAC_ARTIFACT),
+        $translator->boundaryClassification(BaselineCompareReasonCode::CoverageUnproven->value, ReasonTranslator::GOVERNANCE_ARTIFACT_TRUTH_ARTIFACT),
+    ])
+        ->filter()
+        ->unique()
+        ->values()
+        ->all();
+
+    expect($classifications)->toEqualCanonicalizing([
+        PlatformVocabularyGlossary::BOUNDARY_PLATFORM_CORE,
+        PlatformVocabularyGlossary::BOUNDARY_CROSS_DOMAIN_GOVERNANCE,
+        PlatformVocabularyGlossary::BOUNDARY_INTUNE_SPECIFIC,
+    ]);
+});

apps/platform/tests/Feature/Authorization/ReasonTranslationScopeSafetyTest.php

@@ -42,7 +42,9 @@
         ->assertSuccessful()
         ->assertSee('Permission required')
         ->assertSee('The initiating actor no longer has the capability required for this queued run.')
-        ->assertSee('Review workspace or tenant access before retrying.');
+        ->assertSee('Review workspace or tenant access before retrying.')
+        ->assertDontSee('execution_denial')
+        ->assertDontSee('platform_core');
 });
 
 it('returns not found before any translated guidance can leak to non-members', function (): void {

apps/platform/tests/Feature/Baselines/BaselineCompareExecutionGuardTest.php

@@ -2,17 +2,29 @@
 
 declare(strict_types=1);
 
+require_once __DIR__.'/Support/FakeCompareStrategy.php';
+
 use App\Jobs\CompareBaselineToTenantJob;
 use App\Models\BaselineProfile;
 use App\Models\BaselineSnapshot;
+use App\Models\BaselineSnapshotItem;
+use App\Models\BaselineTenantAssignment;
+use App\Models\InventoryItem;
 use App\Models\OperationRun;
+use App\Services\Baselines\BaselineCompareService;
 use App\Services\Baselines\BaselineSnapshotIdentity;
 use App\Services\Intune\AuditLogger;
 use App\Services\OperationRunService;
+use App\Support\Baselines\BaselineCompareReasonCode;
 use App\Support\Baselines\BaselineReasonCodes;
+use App\Support\Baselines\Compare\CompareStrategyRegistry;
+use App\Support\Governance\GovernanceSubjectTaxonomyRegistry;
 use App\Support\OperationRunOutcome;
 use App\Support\OperationRunStatus;
 use App\Support\OperationRunType;
+use Illuminate\Support\Facades\Queue;
+use Tests\Feature\Baselines\Support\FailingCompareStrategy;
+use Tests\Feature\Baselines\Support\FakeGovernanceSubjectTaxonomyRegistry;
 
 it('blocks compare execution when the queued snapshot is incomplete', function (): void {
     [$user, $tenant] = createUserWithTenant(role: 'owner');
@@ -113,3 +125,86 @@
         ->and(data_get($context, 'baseline_compare.latest_attempted_snapshot_id'))->toBe((int) $currentSnapshot->getKey())
         ->and(data_get($run->failure_summary, '0.reason_code'))->toBe(BaselineReasonCodes::COMPARE_SNAPSHOT_SUPERSEDED);
 });
+
+it('marks compare runs as partially succeeded when strategy-owned processing fails before subject classification completes', function (): void {
+    Queue::fake();
+
+    [$user, $tenant] = createUserWithTenant(role: 'owner');
+
+    app()->instance(GovernanceSubjectTaxonomyRegistry::class, new FakeGovernanceSubjectTaxonomyRegistry);
+    app()->instance(CompareStrategyRegistry::class, new CompareStrategyRegistry([
+        app(FailingCompareStrategy::class),
+    ]));
+
+    $profile = BaselineProfile::factory()->active()->create([
+        'workspace_id' => (int) $tenant->workspace_id,
+        'scope_jsonb' => [
+            'version' => 2,
+            'entries' => [[
+                'domain_key' => 'entra',
+                'subject_class' => 'control',
+                'subject_type_keys' => ['conditionalAccessPolicy'],
+                'filters' => [],
+            ]],
+        ],
+    ]);
+
+    $snapshot = BaselineSnapshot::factory()->create([
+        'workspace_id' => (int) $tenant->workspace_id,
+        'baseline_profile_id' => (int) $profile->getKey(),
+        'captured_at' => now()->subMinute(),
+    ]);
+
+    $profile->update(['active_snapshot_id' => (int) $snapshot->getKey()]);
+
+    BaselineTenantAssignment::factory()->create([
+        'workspace_id' => (int) $tenant->workspace_id,
+        'tenant_id' => (int) $tenant->getKey(),
+        'baseline_profile_id' => (int) $profile->getKey(),
+    ]);
+
+    BaselineSnapshotItem::factory()->create([
+        'baseline_snapshot_id' => (int) $snapshot->getKey(),
+        'subject_type' => 'control',
+        'subject_external_id' => 'conditional-access-policy-1',
+        'subject_key' => 'conditional-access-policy-1',
+        'policy_type' => 'conditionalAccessPolicy',
+        'baseline_hash' => hash('sha256', 'baseline'),
+        'meta_jsonb' => ['display_name' => 'Conditional Access Policy'],
+    ]);
+
+    $inventorySyncRun = createInventorySyncOperationRunWithCoverage($tenant, ['conditionalAccessPolicy' => 'succeeded']);
+
+    InventoryItem::factory()->create([
+        'tenant_id' => (int) $tenant->getKey(),
+        'workspace_id' => (int) $tenant->workspace_id,
+        'external_id' => 'conditional-access-policy-1',
+        'policy_type' => 'conditionalAccessPolicy',
+        'display_name' => 'Conditional Access Policy',
+        'meta_jsonb' => ['display_name' => 'Conditional Access Policy'],
+        'last_seen_operation_run_id' => (int) $inventorySyncRun->getKey(),
+        'last_seen_at' => now(),
+    ]);
+
+    $result = app(BaselineCompareService::class)->startCompare($tenant, $user);
+
+    expect($result['ok'])->toBeTrue();
+
+    /** @var OperationRun $run */
+    $run = $result['run'];
+
+    (new CompareBaselineToTenantJob($run))->handle(
+        app(BaselineSnapshotIdentity::class),
+        app(AuditLogger::class),
+        app(OperationRunService::class),
+    );
+
+    $run->refresh();
+
+    expect($run->outcome)->toBe(OperationRunOutcome::PartiallySucceeded->value)
+        ->and(data_get($run->context, 'baseline_compare.reason_code'))->toBe(BaselineCompareReasonCode::StrategyFailed->value)
+        ->and(data_get($run->context, 'baseline_compare.strategy.execution_diagnostics.failed'))->toBeTrue()
+        ->and(data_get($run->context, 'baseline_compare.strategy.execution_diagnostics.exception_class'))->toBe(RuntimeException::class)
+        ->and(data_get($run->context, 'baseline_compare.strategy.state_counts'))->toBe([])
+        ->and(data_get($run->context, 'baseline_compare.evidence_gaps.by_reason.strategy_failed'))->toBe(1);
+});

apps/platform/tests/Feature/Baselines/BaselineCompareMatrixBuilderTest.php

@@ -215,7 +215,7 @@
         ->and($cellsByTenant[(int) $ambiguousTenant->getKey()]['reasonSummary'] ?? null)->toBe('Ambiguous Match')
         ->and($cellsByTenant[(int) $notComparedTenant->getKey()]['state'] ?? null)->toBe('not_compared')
         ->and($cellsByTenant[(int) $notComparedTenant->getKey()]['attentionLevel'] ?? null)->toBe('refresh_recommended')
-        ->and($cellsByTenant[(int) $notComparedTenant->getKey()]['reasonSummary'] ?? null)->toContain('Policy type coverage was not proven')
+        ->and($cellsByTenant[(int) $notComparedTenant->getKey()]['reasonSummary'] ?? null)->toContain('Governed subject coverage was not proven')
         ->and($cellsByTenant[(int) $staleTenant->getKey()]['state'] ?? null)->toBe('stale_result')
         ->and($cellsByTenant[(int) $staleTenant->getKey()]['freshnessState'] ?? null)->toBe('stale')
         ->and($cellsByTenant[(int) $staleTenant->getKey()]['trustLevel'] ?? null)->toBe('limited_confidence')

apps/platform/tests/Feature/Baselines/BaselineCompareMatrixCompareAllActionTest.php

@@ -2,16 +2,24 @@
 
 declare(strict_types=1);
 
+require_once __DIR__.'/Support/FakeCompareStrategy.php';
+
 use App\Filament\Pages\BaselineCompareMatrix;
 use App\Jobs\CompareBaselineToTenantJob;
 use App\Models\OperationRun;
 use App\Models\Tenant;
 use App\Services\Baselines\BaselineCompareService;
+use App\Support\Baselines\BaselineReasonCodes;
+use App\Support\Baselines\Compare\CompareStrategyRegistry;
+use App\Support\Baselines\Compare\IntuneCompareStrategy;
+use App\Support\Governance\GovernanceSubjectTaxonomyRegistry;
 use App\Support\OperationRunOutcome;
 use App\Support\OperationRunStatus;
 use Illuminate\Foundation\Testing\RefreshDatabase;
 use Illuminate\Support\Facades\Queue;
 use Livewire\Livewire;
+use Tests\Feature\Baselines\Support\FakeCompareStrategy;
+use Tests\Feature\Baselines\Support\FakeGovernanceSubjectTaxonomyRegistry;
 use Tests\Feature\Concerns\BuildsBaselineCompareMatrixFixtures;
 
 uses(RefreshDatabase::class, BuildsBaselineCompareMatrixFixtures::class);
@@ -93,3 +101,82 @@
         ->whereNull('tenant_id')
         ->count())->toBe(0);
 });
+
+it('blocks visible assignment fanout when the baseline scope spans multiple compare strategy families', function (): void {
+    Queue::fake();
+
+    $fixture = $this->makeBaselineCompareMatrixFixture();
+
+    app()->instance(GovernanceSubjectTaxonomyRegistry::class, new FakeGovernanceSubjectTaxonomyRegistry);
+    app()->instance(CompareStrategyRegistry::class, new CompareStrategyRegistry([
+        app(IntuneCompareStrategy::class),
+        app(FakeCompareStrategy::class),
+    ]));
+
+    $fixture['profile']->update([
+        'scope_jsonb' => [
+            'version' => 2,
+            'entries' => [
+                [
+                    'domain_key' => 'intune',
+                    'subject_class' => 'policy',
+                    'subject_type_keys' => ['deviceConfiguration'],
+                    'filters' => [],
+                ],
+                [
+                    'domain_key' => 'entra',
+                    'subject_class' => 'control',
+                    'subject_type_keys' => ['conditionalAccessPolicy'],
+                    'filters' => [],
+                ],
+            ],
+        ],
+    ]);
+
+    $result = app(BaselineCompareService::class)->startCompareForVisibleAssignments($fixture['profile'], $fixture['user']);
+
+    expect($result['visibleAssignedTenantCount'])->toBe(2)
+        ->and($result['queuedCount'])->toBe(0)
+        ->and($result['alreadyQueuedCount'])->toBe(0)
+        ->and($result['blockedCount'])->toBe(2)
+        ->and(collect($result['targets'])->pluck('reasonCode')->unique()->values()->all())
+        ->toBe([BaselineReasonCodes::COMPARE_MIXED_SCOPE]);
+
+    Queue::assertNotPushed(CompareBaselineToTenantJob::class);
+});
+
+it('blocks visible assignment fanout when the baseline scope has no compatible compare strategy family', function (): void {
+    Queue::fake();
+
+    $fixture = $this->makeBaselineCompareMatrixFixture();
+
+    app()->instance(GovernanceSubjectTaxonomyRegistry::class, new FakeGovernanceSubjectTaxonomyRegistry);
+    app()->instance(CompareStrategyRegistry::class, new CompareStrategyRegistry([
+        app(IntuneCompareStrategy::class),
+    ]));
+
+    $fixture['profile']->update([
+        'scope_jsonb' => [
+            'version' => 2,
+            'entries' => [
+                [
+                    'domain_key' => 'entra',
+                    'subject_class' => 'control',
+                    'subject_type_keys' => ['conditionalAccessPolicy'],
+                    'filters' => [],
+                ],
+            ],
+        ],
+    ]);
+
+    $result = app(BaselineCompareService::class)->startCompareForVisibleAssignments($fixture['profile'], $fixture['user']);
+
+    expect($result['visibleAssignedTenantCount'])->toBe(2)
+        ->and($result['queuedCount'])->toBe(0)
+        ->and($result['alreadyQueuedCount'])->toBe(0)
+        ->and($result['blockedCount'])->toBe(2)
+        ->and(collect($result['targets'])->pluck('reasonCode')->unique()->values()->all())
+        ->toBe([BaselineReasonCodes::COMPARE_UNSUPPORTED_SCOPE]);
+
+    Queue::assertNotPushed(CompareBaselineToTenantJob::class);
+});

apps/platform/tests/Feature/Baselines/BaselineComparePreconditionsTest.php

@@ -1,15 +1,22 @@
 <?php
 
+require_once __DIR__.'/Support/FakeCompareStrategy.php';
+
 use App\Jobs\CompareBaselineToTenantJob;
 use App\Models\BaselineProfile;
 use App\Models\BaselineSnapshot;
 use App\Models\BaselineTenantAssignment;
 use App\Models\OperationRun;
 use App\Services\Baselines\BaselineCompareService;
+use App\Support\Baselines\Compare\CompareStrategyRegistry;
 use App\Support\Baselines\BaselineProfileStatus;
 use App\Support\Baselines\BaselineReasonCodes;
+use App\Support\Baselines\Compare\IntuneCompareStrategy;
+use App\Support\Governance\GovernanceSubjectTaxonomyRegistry;
 use App\Support\OperationRunType;
 use Illuminate\Support\Facades\Queue;
+use Tests\Feature\Baselines\Support\FakeCompareStrategy;
+use Tests\Feature\Baselines\Support\FakeGovernanceSubjectTaxonomyRegistry;
 
 // --- T040: Compare precondition 422 tests ---
 
@@ -217,6 +224,158 @@
     Queue::assertPushed(CompareBaselineToTenantJob::class);
 });
 
+it('rejects compare when canonical scope spans multiple compare strategy families', function (): void {
+    Queue::fake();
+
+    [$user, $tenant] = createUserWithTenant(role: 'owner');
+
+    app()->instance(GovernanceSubjectTaxonomyRegistry::class, new FakeGovernanceSubjectTaxonomyRegistry);
+    app()->instance(CompareStrategyRegistry::class, new CompareStrategyRegistry([
+        app(IntuneCompareStrategy::class),
+        app(FakeCompareStrategy::class),
+    ]));
+
+    $profile = BaselineProfile::factory()->active()->create([
+        'workspace_id' => $tenant->workspace_id,
+        'scope_jsonb' => [
+            'version' => 2,
+            'entries' => [
+                [
+                    'domain_key' => 'intune',
+                    'subject_class' => 'policy',
+                    'subject_type_keys' => ['deviceConfiguration'],
+                    'filters' => [],
+                ],
+                [
+                    'domain_key' => 'entra',
+                    'subject_class' => 'control',
+                    'subject_type_keys' => ['conditionalAccessPolicy'],
+                    'filters' => [],
+                ],
+            ],
+        ],
+    ]);
+
+    $snapshot = BaselineSnapshot::factory()->create([
+        'workspace_id' => $tenant->workspace_id,
+        'baseline_profile_id' => $profile->getKey(),
+    ]);
+
+    $profile->update(['active_snapshot_id' => $snapshot->getKey()]);
+
+    BaselineTenantAssignment::create([
+        'workspace_id' => (int) $tenant->workspace_id,
+        'tenant_id' => (int) $tenant->getKey(),
+        'baseline_profile_id' => (int) $profile->getKey(),
+    ]);
+
+    $service = app(BaselineCompareService::class);
+    $result = $service->startCompare($tenant, $user);
+
+    expect($result['ok'])->toBeFalse();
+    expect($result['reason_code'])->toBe(BaselineReasonCodes::COMPARE_MIXED_SCOPE);
+
+    Queue::assertNotPushed(CompareBaselineToTenantJob::class);
+    expect(OperationRun::query()->where('type', OperationRunType::BaselineCompare->value)->count())->toBe(0);
+});
+
+it('rejects compare when canonical scope uses an inactive subject type', function (): void {
+    Queue::fake();
+
+    [$user, $tenant] = createUserWithTenant(role: 'owner');
+
+    $profile = BaselineProfile::factory()->active()->create([
+        'workspace_id' => $tenant->workspace_id,
+        'scope_jsonb' => ['policy_types' => ['deviceConfiguration'], 'foundation_types' => []],
+    ]);
+
+    BaselineProfile::query()
+        ->whereKey($profile->getKey())
+        ->update([
+            'scope_jsonb' => json_encode([
+                'version' => 2,
+                'entries' => [
+                    [
+                        'domain_key' => 'platform_foundation',
+                        'subject_class' => 'configuration_resource',
+                        'subject_type_keys' => ['intuneRoleAssignment'],
+                        'filters' => [],
+                    ],
+                ],
+            ], JSON_THROW_ON_ERROR),
+        ]);
+
+    $snapshot = BaselineSnapshot::factory()->create([
+        'workspace_id' => $tenant->workspace_id,
+        'baseline_profile_id' => $profile->getKey(),
+    ]);
+
+    $profile->update(['active_snapshot_id' => $snapshot->getKey()]);
+
+    BaselineTenantAssignment::create([
+        'workspace_id' => (int) $tenant->workspace_id,
+        'tenant_id' => (int) $tenant->getKey(),
+        'baseline_profile_id' => (int) $profile->getKey(),
+    ]);
+
+    $service = app(BaselineCompareService::class);
+    $result = $service->startCompare($tenant, $user);
+
+    expect($result['ok'])->toBeFalse();
+    expect($result['reason_code'])->toBe(BaselineReasonCodes::COMPARE_INVALID_SCOPE);
+
+    Queue::assertNotPushed(CompareBaselineToTenantJob::class);
+    expect(OperationRun::query()->where('type', OperationRunType::BaselineCompare->value)->count())->toBe(0);
+});
+
+it('rejects compare when canonical scope has no compatible compare strategy', function (): void {
+    Queue::fake();
+
+    [$user, $tenant] = createUserWithTenant(role: 'owner');
+
+    app()->instance(GovernanceSubjectTaxonomyRegistry::class, new FakeGovernanceSubjectTaxonomyRegistry);
+    app()->instance(CompareStrategyRegistry::class, new CompareStrategyRegistry([
+        app(IntuneCompareStrategy::class),
+    ]));
+
+    $profile = BaselineProfile::factory()->active()->create([
+        'workspace_id' => $tenant->workspace_id,
+        'scope_jsonb' => [
+            'version' => 2,
+            'entries' => [
+                [
+                    'domain_key' => 'entra',
+                    'subject_class' => 'control',
+                    'subject_type_keys' => ['conditionalAccessPolicy'],
+                    'filters' => [],
+                ],
+            ],
+        ],
+    ]);
+
+    $snapshot = BaselineSnapshot::factory()->create([
+        'workspace_id' => $tenant->workspace_id,
+        'baseline_profile_id' => $profile->getKey(),
+    ]);
+
+    $profile->update(['active_snapshot_id' => $snapshot->getKey()]);
+
+    BaselineTenantAssignment::create([
+        'workspace_id' => (int) $tenant->workspace_id,
+        'tenant_id' => (int) $tenant->getKey(),
+        'baseline_profile_id' => (int) $profile->getKey(),
+    ]);
+
+    $service = app(BaselineCompareService::class);
+    $result = $service->startCompare($tenant, $user);
+
+    expect($result['ok'])->toBeFalse();
+    expect($result['reason_code'])->toBe(BaselineReasonCodes::COMPARE_UNSUPPORTED_SCOPE);
+
+    Queue::assertNotPushed(CompareBaselineToTenantJob::class);
+    expect(OperationRun::query()->where('type', OperationRunType::BaselineCompare->value)->count())->toBe(0);
+});
+
 it('uses an explicit snapshot override instead of baseline_profiles.active_snapshot_id when provided', function () {
     Queue::fake();
 

apps/platform/tests/Feature/Baselines/BaselineCompareStrategySelectionTest.php

@@ -0,0 +1,160 @@
+<?php
+
+declare(strict_types=1);
+
+require_once __DIR__.'/Support/FakeCompareStrategy.php';
+
+use App\Jobs\CompareBaselineToTenantJob;
+use App\Models\BaselineProfile;
+use App\Models\BaselineSnapshot;
+use App\Models\BaselineTenantAssignment;
+use App\Models\Finding;
+use App\Models\InventoryItem;
+use App\Models\OperationRun;
+use App\Services\Baselines\BaselineCompareService;
+use App\Services\Baselines\BaselineSnapshotIdentity;
+use App\Services\Intune\AuditLogger;
+use App\Services\OperationRunService;
+use App\Support\Baselines\Compare\CompareStrategyRegistry;
+use App\Support\OperationRunOutcome;
+use App\Support\OperationRunStatus;
+use App\Support\OperationRunType;
+use App\Support\Governance\GovernanceSubjectTaxonomyRegistry;
+use Illuminate\Foundation\Testing\RefreshDatabase;
+use Illuminate\Support\Facades\Queue;
+use Tests\Feature\Baselines\Support\FakeCompareStrategy;
+use Tests\Feature\Baselines\Support\FakeGovernanceSubjectTaxonomyRegistry;
+
+uses(RefreshDatabase::class);
+
+it('runs a future-domain compare strategy through the shared lifecycle without implicit intune fallback', function (): void {
+    Queue::fake();
+
+    [$user, $tenant] = createUserWithTenant(role: 'owner');
+
+    app()->instance(GovernanceSubjectTaxonomyRegistry::class, new FakeGovernanceSubjectTaxonomyRegistry);
+    app()->instance(CompareStrategyRegistry::class, new CompareStrategyRegistry([
+        app(FakeCompareStrategy::class),
+    ]));
+
+    $profile = BaselineProfile::factory()->active()->create([
+        'workspace_id' => (int) $tenant->workspace_id,
+        'scope_jsonb' => [
+            'version' => 2,
+            'entries' => [[
+                'domain_key' => 'entra',
+                'subject_class' => 'control',
+                'subject_type_keys' => ['conditionalAccessPolicy'],
+                'filters' => [],
+            ]],
+        ],
+    ]);
+
+    $snapshot = BaselineSnapshot::factory()->create([
+        'workspace_id' => (int) $tenant->workspace_id,
+        'baseline_profile_id' => (int) $profile->getKey(),
+        'captured_at' => now()->subMinute(),
+    ]);
+
+    $profile->update(['active_snapshot_id' => (int) $snapshot->getKey()]);
+
+    BaselineTenantAssignment::factory()->create([
+        'workspace_id' => (int) $tenant->workspace_id,
+        'tenant_id' => (int) $tenant->getKey(),
+        'baseline_profile_id' => (int) $profile->getKey(),
+    ]);
+
+    $displayName = 'Conditional Access Global Block';
+    $externalId = 'conditional-access-policy-1';
+    $subjectKey = app(BaselineSnapshotIdentity::class)->subjectKey(
+        policyType: 'conditionalAccessPolicy',
+        displayName: $displayName,
+        subjectExternalId: $externalId,
+    ) ?? $externalId;
+
+    $baselineMeta = [
+        'display_name' => $displayName,
+        'conditions' => ['users' => ['includeGuestsOrExternalUsers' => true]],
+    ];
+    $currentMeta = [
+        'display_name' => $displayName,
+        'conditions' => ['users' => ['includeGuestsOrExternalUsers' => false]],
+    ];
+
+    $baselineHash = app(BaselineSnapshotIdentity::class)->hashItemContent(
+        policyType: 'conditionalAccessPolicy',
+        subjectExternalId: $externalId,
+        metaJsonb: $baselineMeta,
+    );
+
+    \App\Models\BaselineSnapshotItem::factory()->create([
+        'baseline_snapshot_id' => (int) $snapshot->getKey(),
+        'subject_type' => 'control',
+        'subject_external_id' => $externalId,
+        'subject_key' => $subjectKey,
+        'policy_type' => 'conditionalAccessPolicy',
+        'baseline_hash' => $baselineHash,
+        'meta_jsonb' => $baselineMeta,
+    ]);
+
+    $inventorySyncRun = OperationRun::factory()->create([
+        'tenant_id' => (int) $tenant->getKey(),
+        'workspace_id' => (int) $tenant->workspace_id,
+        'type' => OperationRunType::InventorySync->value,
+        'status' => OperationRunStatus::Completed->value,
+        'outcome' => OperationRunOutcome::Succeeded->value,
+        'completed_at' => now(),
+        'context' => [
+            'inventory' => [
+                'coverage' => [
+                    'policy_types' => [
+                        'conditionalAccessPolicy' => ['status' => 'succeeded'],
+                    ],
+                    'foundation_types' => [],
+                ],
+            ],
+        ],
+    ]);
+
+    InventoryItem::factory()->create([
+        'tenant_id' => (int) $tenant->getKey(),
+        'workspace_id' => (int) $tenant->workspace_id,
+        'external_id' => $externalId,
+        'policy_type' => 'conditionalAccessPolicy',
+        'display_name' => $displayName,
+        'meta_jsonb' => $currentMeta,
+        'last_seen_operation_run_id' => (int) $inventorySyncRun->getKey(),
+        'last_seen_at' => now(),
+    ]);
+
+    $service = app(BaselineCompareService::class);
+    $result = $service->startCompare($tenant, $user);
+
+    expect($result['ok'] ?? false)->toBeTrue();
+    Queue::assertPushed(CompareBaselineToTenantJob::class);
+
+    /** @var OperationRun $run */
+    $run = $result['run'];
+
+    (new CompareBaselineToTenantJob($run))->handle(
+        app(\App\Services\Baselines\BaselineSnapshotIdentity::class),
+        app(AuditLogger::class),
+        app(OperationRunService::class),
+    );
+
+    $run->refresh();
+
+    expect($run->status)->toBe(OperationRunStatus::Completed->value)
+        ->and($run->outcome)->toBe(OperationRunOutcome::Succeeded->value)
+        ->and(data_get($run->context, 'baseline_compare.strategy.key'))->toBe('future_control')
+        ->and(data_get($run->context, 'baseline_compare.strategy.selection_state'))->toBe('supported')
+        ->and(data_get($run->context, 'findings.counts_by_change_type.different_version'))->toBe(1)
+        ->and(data_get($run->context, 'result.findings_total'))->toBe(1);
+
+    $finding = Finding::query()->where('tenant_id', (int) $tenant->getKey())->first();
+
+    expect($finding)->not->toBeNull()
+        ->and($finding?->subject_type)->toBe('control')
+        ->and(data_get($finding?->evidence_jsonb, 'summary.kind'))->toBe('control_snapshot')
+        ->and(data_get($finding?->evidence_jsonb, 'policy_type'))->toBe('conditionalAccessPolicy');
+});

apps/platform/tests/Feature/Baselines/Support/FakeCompareStrategy.php

@@ -0,0 +1,454 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Tests\Feature\Baselines\Support;
+
+use App\Models\Tenant;
+use App\Services\Baselines\Evidence\EvidenceProvenance;
+use App\Services\Baselines\Evidence\ResolvedEvidence;
+use App\Support\Baselines\Compare\CompareFindingCandidate;
+use App\Support\Baselines\Compare\CompareOrchestrationContext;
+use App\Support\Baselines\Compare\CompareState;
+use App\Support\Baselines\Compare\CompareStrategy;
+use App\Support\Baselines\Compare\CompareStrategyCapability;
+use App\Support\Baselines\Compare\CompareStrategyKey;
+use App\Support\Baselines\Compare\CompareSubjectIdentity;
+use App\Support\Baselines\Compare\CompareSubjectProjection;
+use App\Support\Baselines\Compare\CompareSubjectResult;
+use App\Support\Baselines\OperatorActionCategory;
+use App\Support\Baselines\ResolutionOutcome;
+use App\Support\Baselines\ResolutionPath;
+use App\Support\Baselines\SubjectClass;
+use App\Support\Governance\GovernanceDomainKey;
+use App\Support\Governance\GovernanceSubjectClass;
+use App\Support\Governance\GovernanceSubjectTaxonomyRegistry;
+use App\Support\Governance\GovernanceSubjectType;
+
+final class FakeCompareStrategy implements CompareStrategy
+{
+    public function key(): CompareStrategyKey
+    {
+        return CompareStrategyKey::from('future_control');
+    }
+
+    public function capabilities(): array
+    {
+        return [
+            new CompareStrategyCapability(
+                strategyKey: $this->key(),
+                domainKeys: [GovernanceDomainKey::Entra->value],
+                subjectClasses: [GovernanceSubjectClass::Control->value],
+                subjectTypeKeys: ['conditionalAccessPolicy'],
+            ),
+        ];
+    }
+
+    public function compare(
+        CompareOrchestrationContext $context,
+        Tenant $tenant,
+        array $baselineItems,
+        array $currentItems,
+        array $resolvedCurrentEvidence,
+        array $severityMapping,
+    ): array {
+        $subjectResults = [];
+
+        foreach ($baselineItems as $key => $baselineItem) {
+            $currentItem = $currentItems[$key] ?? null;
+
+            if (! is_array($currentItem)) {
+                $subjectResults[] = $this->driftResult(
+                    context: $context,
+                    baselineItem: $baselineItem,
+                    currentItem: null,
+                    currentEvidence: null,
+                    changeType: 'missing_policy',
+                    severity: 'high',
+                );
+
+                continue;
+            }
+
+            $currentEvidence = $resolvedCurrentEvidence[$key] ?? null;
+
+            if (! $currentEvidence instanceof ResolvedEvidence) {
+                $subjectResults[] = $this->gapResult(
+                    policyType: (string) $baselineItem['policy_type'],
+                    subjectKey: (string) $baselineItem['subject_key'],
+                    externalSubjectId: (string) $baselineItem['subject_external_id'],
+                    operatorLabel: (string) (($currentItem['meta_jsonb']['display_name'] ?? $baselineItem['meta_jsonb']['display_name'] ?? $baselineItem['subject_key']) ?: $baselineItem['subject_key']),
+                    compareState: CompareState::Incomplete,
+                    reasonCode: 'missing_current',
+                    baselineAvailability: 'available',
+                    currentStateAvailability: 'unknown',
+                    trustLevel: 'unusable',
+                    evidenceQuality: 'missing',
+                );
+
+                continue;
+            }
+
+            $baselineMeta = is_array($baselineItem['meta_jsonb'] ?? null) ? $baselineItem['meta_jsonb'] : [];
+            $currentMeta = is_array($currentItem['meta_jsonb'] ?? null) ? $currentItem['meta_jsonb'] : [];
+
+            if ($this->metaFingerprint($baselineMeta) !== $this->metaFingerprint($currentMeta)) {
+                $subjectResults[] = $this->driftResult(
+                    context: $context,
+                    baselineItem: $baselineItem,
+                    currentItem: $currentItem,
+                    currentEvidence: $currentEvidence,
+                    changeType: 'different_version',
+                    severity: 'medium',
+                );
+
+                continue;
+            }
+
+            $subjectResults[] = new CompareSubjectResult(
+                subjectIdentity: $this->identity(
+                    policyType: (string) $baselineItem['policy_type'],
+                    externalSubjectId: (string) $baselineItem['subject_external_id'],
+                    subjectKey: (string) $baselineItem['subject_key'],
+                ),
+                projection: $this->projection(
+                    policyType: (string) $baselineItem['policy_type'],
+                    operatorLabel: (string) (($currentItem['meta_jsonb']['display_name'] ?? $baselineItem['meta_jsonb']['display_name'] ?? $baselineItem['subject_key']) ?: $baselineItem['subject_key']),
+                ),
+                baselineAvailability: 'available',
+                currentStateAvailability: 'available',
+                compareState: CompareState::NoDrift,
+                trustLevel: 'trustworthy',
+                evidenceQuality: $currentEvidence->fidelity,
+            );
+        }
+
+        foreach ($currentItems as $key => $currentItem) {
+            if (array_key_exists($key, $baselineItems)) {
+                continue;
+            }
+
+            $currentEvidence = $resolvedCurrentEvidence[$key] ?? null;
+
+            if (! $currentEvidence instanceof ResolvedEvidence) {
+                $subjectResults[] = $this->gapResult(
+                    policyType: (string) $currentItem['policy_type'],
+                    subjectKey: (string) $currentItem['subject_key'],
+                    externalSubjectId: (string) $currentItem['subject_external_id'],
+                    operatorLabel: (string) (($currentItem['meta_jsonb']['display_name'] ?? $currentItem['subject_key']) ?: $currentItem['subject_key']),
+                    compareState: CompareState::Incomplete,
+                    reasonCode: 'missing_current',
+                    baselineAvailability: 'missing',
+                    currentStateAvailability: 'unknown',
+                    trustLevel: 'unusable',
+                    evidenceQuality: 'missing',
+                );
+
+                continue;
+            }
+
+            $subjectResults[] = $this->driftResult(
+                context: $context,
+                baselineItem: null,
+                currentItem: $currentItem,
+                currentEvidence: $currentEvidence,
+                changeType: 'unexpected_policy',
+                severity: 'low',
+            );
+        }
+
+        return [
+            'subject_results' => $subjectResults,
+            'diagnostics' => [
+                'strategy_family' => 'future_control',
+                'state_counts' => [
+                    'drift' => count(array_filter($subjectResults, static fn (CompareSubjectResult $result): bool => $result->compareState === CompareState::Drift)),
+                ],
+            ],
+        ];
+    }
+
+    /**
+     * @param  array<string, mixed>  $meta
+     */
+    private function metaFingerprint(array $meta): string
+    {
+        unset($meta['display_name'], $meta['category'], $meta['platform']);
+
+        return hash('sha256', json_encode($this->sortRecursive($meta), JSON_THROW_ON_ERROR | JSON_UNESCAPED_SLASHES | JSON_UNESCAPED_UNICODE));
+    }
+
+    /**
+     * @param  array<string, mixed>  $value
+     * @return array<string, mixed>
+     */
+    private function sortRecursive(array $value): array
+    {
+        foreach ($value as $key => $nestedValue) {
+            if (! is_array($nestedValue)) {
+                continue;
+            }
+
+            $value[$key] = $this->sortRecursive($nestedValue);
+        }
+
+        ksort($value, SORT_STRING);
+
+        return $value;
+    }
+
+    private function driftResult(
+        CompareOrchestrationContext $context,
+        ?array $baselineItem,
+        ?array $currentItem,
+        ?ResolvedEvidence $currentEvidence,
+        string $changeType,
+        string $severity,
+    ): CompareSubjectResult {
+        $source = $baselineItem ?? $currentItem ?? [];
+        $policyType = (string) ($source['policy_type'] ?? 'conditionalAccessPolicy');
+        $subjectKey = (string) ($source['subject_key'] ?? 'unknown');
+        $externalSubjectId = (string) ($source['subject_external_id'] ?? 'unknown');
+        $operatorLabel = (string) ((($currentItem['meta_jsonb']['display_name'] ?? null) ?: ($baselineItem['meta_jsonb']['display_name'] ?? null) ?: $subjectKey) ?: $subjectKey);
+        $fidelity = $currentEvidence?->fidelity ?? EvidenceProvenance::FidelityMeta;
+        $baselineProvenance = EvidenceProvenance::build(
+            fidelity: EvidenceProvenance::FidelityMeta,
+            source: EvidenceProvenance::SourceInventory,
+            observedAt: null,
+            observedOperationRunId: null,
+        );
+        $currentProvenance = $currentEvidence?->tenantProvenance() ?? EvidenceProvenance::build(
+            fidelity: $fidelity,
+            source: EvidenceProvenance::SourceInventory,
+            observedAt: null,
+            observedOperationRunId: $context->inventorySyncRunId(),
+        );
+
+        return new CompareSubjectResult(
+            subjectIdentity: $this->identity($policyType, $externalSubjectId, $subjectKey),
+            projection: $this->projection($policyType, $operatorLabel),
+            baselineAvailability: $baselineItem === null ? 'missing' : 'available',
+            currentStateAvailability: $currentItem === null ? 'missing' : 'available',
+            compareState: CompareState::Drift,
+            trustLevel: $fidelity === EvidenceProvenance::FidelityContent ? 'trustworthy' : 'limited_confidence',
+            evidenceQuality: $fidelity,
+            severityRecommendation: $severity,
+            findingCandidate: new CompareFindingCandidate(
+                changeType: $changeType,
+                severity: $severity,
+                fingerprintBasis: [
+                    'policy_type' => $policyType,
+                    'subject_key' => $subjectKey,
+                    'change_type' => $changeType,
+                ],
+                evidencePayload: [
+                    'change_type' => $changeType,
+                    'policy_type' => $policyType,
+                    'subject_key' => $subjectKey,
+                    'display_name' => $operatorLabel,
+                    'summary' => ['kind' => 'control_snapshot'],
+                    'baseline' => [
+                        'hash' => $baselineItem['baseline_hash'] ?? null,
+                        'provenance' => $baselineProvenance,
+                    ],
+                    'current' => [
+                        'hash' => $currentEvidence?->hash,
+                        'provenance' => $currentProvenance,
+                    ],
+                    'fidelity' => $fidelity,
+                    'provenance' => [
+                        'baseline_profile_id' => $context->baselineProfileId,
+                        'baseline_snapshot_id' => $context->baselineSnapshotId,
+                        'compare_operation_run_id' => $context->operationRunId,
+                        'inventory_sync_run_id' => $context->inventorySyncRunId(),
+                    ],
+                ],
+            ),
+            diagnostics: [
+                'strategy_key' => $this->key()->value,
+            ],
+        );
+    }
+
+    private function gapResult(
+        string $policyType,
+        string $subjectKey,
+        string $externalSubjectId,
+        string $operatorLabel,
+        CompareState $compareState,
+        string $reasonCode,
+        string $baselineAvailability,
+        string $currentStateAvailability,
+        string $trustLevel,
+        string $evidenceQuality,
+    ): CompareSubjectResult {
+        return new CompareSubjectResult(
+            subjectIdentity: $this->identity($policyType, $externalSubjectId, $subjectKey),
+            projection: $this->projection($policyType, $operatorLabel),
+            baselineAvailability: $baselineAvailability,
+            currentStateAvailability: $currentStateAvailability,
+            compareState: $compareState,
+            trustLevel: $trustLevel,
+            evidenceQuality: $evidenceQuality,
+            diagnostics: [
+                'reason_code' => $reasonCode,
+                'gap_record' => [
+                    'policy_type' => $policyType,
+                    'subject_key' => $subjectKey,
+                    'subject_class' => SubjectClass::Derived->value,
+                    'resolution_path' => ResolutionPath::Derived->value,
+                    'resolution_outcome' => ResolutionOutcome::CaptureFailed->value,
+                    'operator_action_category' => OperatorActionCategory::RunInventorySync->value,
+                    'structural' => false,
+                    'retryable' => $reasonCode === 'missing_current',
+                    'reason_code' => $reasonCode,
+                    'search_text' => strtolower(implode(' ', [$policyType, $subjectKey, $reasonCode])),
+                ],
+            ],
+        );
+    }
+
+    private function identity(string $policyType, string $externalSubjectId, string $subjectKey): CompareSubjectIdentity
+    {
+        return new CompareSubjectIdentity(
+            domainKey: GovernanceDomainKey::Entra->value,
+            subjectClass: GovernanceSubjectClass::Control->value,
+            subjectTypeKey: $policyType,
+            externalSubjectId: $externalSubjectId,
+            subjectKey: $subjectKey,
+        );
+    }
+
+    private function projection(string $policyType, string $operatorLabel): CompareSubjectProjection
+    {
+        return new CompareSubjectProjection(
+            platformSubjectClass: 'control',
+            domainKey: GovernanceDomainKey::Entra->value,
+            subjectTypeKey: $policyType,
+            operatorLabel: $operatorLabel,
+            summaryKind: 'control_snapshot',
+        );
+    }
+}
+
+final class FailingCompareStrategy implements CompareStrategy
+{
+    public function key(): CompareStrategyKey
+    {
+        return CompareStrategyKey::from('failing_control');
+    }
+
+    public function capabilities(): array
+    {
+        return [
+            new CompareStrategyCapability(
+                strategyKey: $this->key(),
+                domainKeys: [GovernanceDomainKey::Entra->value],
+                subjectClasses: [GovernanceSubjectClass::Control->value],
+                subjectTypeKeys: ['conditionalAccessPolicy'],
+            ),
+        ];
+    }
+
+    public function compare(
+        CompareOrchestrationContext $context,
+        Tenant $tenant,
+        array $baselineItems,
+        array $currentItems,
+        array $resolvedCurrentEvidence,
+        array $severityMapping,
+    ): array {
+        throw new \RuntimeException('Synthetic strategy failure for compare testing.');
+    }
+}
+
+final class FakeGovernanceSubjectTaxonomyRegistry
+{
+    private readonly GovernanceSubjectTaxonomyRegistry $inner;
+
+    public function __construct()
+    {
+        $this->inner = new GovernanceSubjectTaxonomyRegistry;
+    }
+
+    public function all(): array
+    {
+        return array_values(array_merge($this->inner->all(), [
+            new GovernanceSubjectType(
+                domainKey: GovernanceDomainKey::Entra,
+                subjectClass: GovernanceSubjectClass::Control,
+                subjectTypeKey: 'conditionalAccessPolicy',
+                label: 'Conditional Access Policy',
+                description: 'Synthetic test-only future domain control',
+                captureSupported: true,
+                compareSupported: true,
+                inventorySupported: true,
+                active: true,
+                supportMode: 'supported',
+                legacyBucket: null,
+            ),
+        ]));
+    }
+
+    public function active(): array
+    {
+        return array_values(array_filter(
+            $this->all(),
+            static fn (GovernanceSubjectType $subjectType): bool => $subjectType->active,
+        ));
+    }
+
+    public function activeLegacyBucketKeys(string $legacyBucket): array
+    {
+        $subjectTypes = array_filter(
+            $this->active(),
+            static fn (GovernanceSubjectType $subjectType): bool => $subjectType->legacyBucket === $legacyBucket,
+        );
+
+        $keys = array_map(
+            static fn (GovernanceSubjectType $subjectType): string => $subjectType->subjectTypeKey,
+            $subjectTypes,
+        );
+
+        sort($keys, SORT_STRING);
+
+        return array_values(array_unique($keys));
+    }
+
+    public function find(string $domainKey, string $subjectTypeKey): ?GovernanceSubjectType
+    {
+        foreach ($this->all() as $subjectType) {
+            if ($subjectType->domainKey->value !== trim($domainKey)) {
+                continue;
+            }
+
+            if ($subjectType->subjectTypeKey !== trim($subjectTypeKey)) {
+                continue;
+            }
+
+            return $subjectType;
+        }
+
+        return null;
+    }
+
+    public function isKnownDomain(string $domainKey): bool
+    {
+        return $this->inner->isKnownDomain($domainKey);
+    }
+
+    public function allowsSubjectClass(string $domainKey, string $subjectClass): bool
+    {
+        return $this->inner->allowsSubjectClass($domainKey, $subjectClass);
+    }
+
+    public function supportsFilters(string $domainKey, string $subjectClass): bool
+    {
+        return $this->inner->supportsFilters($domainKey, $subjectClass);
+    }
+
+    public function groupLabel(string $domainKey, string $subjectClass): string
+    {
+        return $this->inner->groupLabel($domainKey, $subjectClass);
+    }
+}

apps/platform/tests/Feature/Filament/BaselineCompareEvidenceGapTableTest.php

@@ -80,7 +80,7 @@ function baselineCompareEvidenceGapBuckets(): array
     expect($table->isSearchable())->toBeTrue();
     expect($table->getDefaultSortColumn())->toBe('reason_label');
     expect($table->getColumn('reason_label')?->isSearchable())->toBeTrue();
-    expect($table->getColumn('policy_type')?->isSearchable())->toBeTrue();
+    expect($table->getColumn('governed_subject_label')?->isSearchable())->toBeTrue();
     expect($table->getColumn('subject_class_label')?->isSearchable())->toBeTrue();
     expect($table->getColumn('resolution_outcome_label')?->isSearchable())->toBeTrue();
     expect($table->getColumn('operator_action_category_label')?->isSearchable())->toBeTrue();
@@ -90,7 +90,7 @@ function baselineCompareEvidenceGapBuckets(): array
         ->assertSee('WiFi-Corp-Profile')
         ->assertSee('Deleted-Policy-ABC')
         ->assertSee('Reason')
-        ->assertSee('Policy type')
+        ->assertSee('Governed subject')
         ->assertSee('Subject class')
         ->assertSee('Outcome')
         ->assertSee('Next action')
@@ -119,6 +119,7 @@ function baselineCompareEvidenceGapBuckets(): array
         ->assertSee('Retired-Compliance-Policy')
         ->assertDontSee('VPN-Always-On')
         ->filterTable('policy_type', 'deviceCompliancePolicy')
+        ->assertSee('Device Compliance')
         ->assertSee('Retired-Compliance-Policy')
         ->assertDontSee('Deleted-Policy-ABC')
         ->filterTable('operator_action_category', 'run_policy_sync_or_backup')

apps/platform/tests/Feature/Filament/BaselineCompareExplanationSurfaceTest.php

@@ -9,6 +9,7 @@
 use App\Models\OperationRun;
 use App\Support\Baselines\BaselineCompareReasonCode;
 use App\Support\Baselines\BaselineCompareStats;
+use App\Support\ReasonTranslation\ReasonPresenter;
 use App\Support\Ui\OperatorExplanation\ExplanationFamily;
 use Filament\Facades\Filament;
 use Livewire\Livewire;
@@ -74,14 +75,22 @@
     $stats = BaselineCompareStats::forTenant($tenant);
     $explanation = $stats->operatorExplanation();
     $summary = $stats->summaryAssessment();
+    $reasonSemantics = app(ReasonPresenter::class)->semantics(
+        app(ReasonPresenter::class)->forArtifactTruth(BaselineCompareReasonCode::CoverageUnproven->value, 'artifact_truth'),
+    );
 
     expect($explanation->family)->toBe(ExplanationFamily::SuppressedOutput);
+    expect($reasonSemantics)->not->toBeNull();
 
     Livewire::actingAs($user)
         ->test(BaselineCompareLanding::class)
         ->assertSee($summary->headline)
         ->assertSee($explanation->trustworthinessLabel())
         ->assertSee($summary->nextActionLabel())
+        ->assertSee('Reason owner')
+        ->assertSee($reasonSemantics['owner_label'])
+        ->assertSee('Platform reason family')
+        ->assertSee($reasonSemantics['family_label'])
         ->assertSee('Findings shown')
         ->assertSee('Evidence gaps');
 });

apps/platform/tests/Feature/Filament/BaselineCompareLandingStartSurfaceTest.php

@@ -1,5 +1,7 @@
 <?php
 
+require_once dirname(__DIR__).'/Baselines/Support/FakeCompareStrategy.php';
+
 use App\Filament\Pages\BaselineCompareLanding;
 use App\Jobs\CompareBaselineToTenantJob;
 use App\Livewire\BulkOperationProgress;
@@ -7,6 +9,9 @@
 use App\Models\BaselineSnapshot;
 use App\Models\BaselineTenantAssignment;
 use App\Models\OperationRun;
+use App\Support\Baselines\Compare\CompareStrategyRegistry;
+use App\Support\Baselines\Compare\IntuneCompareStrategy;
+use App\Support\Governance\GovernanceSubjectTaxonomyRegistry;
 use App\Support\OperationRunOutcome;
 use App\Support\OperationRunStatus;
 use App\Support\OperationRunType;
@@ -15,6 +20,8 @@
 use Filament\Facades\Filament;
 use Illuminate\Support\Facades\Queue;
 use Livewire\Livewire;
+use Tests\Feature\Baselines\Support\FakeCompareStrategy;
+use Tests\Feature\Baselines\Support\FakeGovernanceSubjectTaxonomyRegistry;
 
 it('redirects unauthenticated users (302)', function (): void {
     [$user, $tenant] = createUserWithTenant(role: 'owner');
@@ -186,6 +193,64 @@
     expect(OperationRun::query()->where('type', 'baseline_compare')->count())->toBe(0);
 });
 
+it('shows mixed-strategy compare rejection truth on the tenant landing surface', function (): void {
+    Queue::fake();
+
+    [$user, $tenant] = createUserWithTenant(role: 'owner');
+    $this->actingAs($user);
+
+    $tenant->makeCurrent();
+    Filament::setTenant($tenant, true);
+
+    app()->instance(GovernanceSubjectTaxonomyRegistry::class, new FakeGovernanceSubjectTaxonomyRegistry);
+    app()->instance(CompareStrategyRegistry::class, new CompareStrategyRegistry([
+        app(IntuneCompareStrategy::class),
+        app(FakeCompareStrategy::class),
+    ]));
+
+    $profile = BaselineProfile::factory()->active()->create([
+        'workspace_id' => (int) $tenant->workspace_id,
+        'scope_jsonb' => [
+            'version' => 2,
+            'entries' => [
+                [
+                    'domain_key' => 'intune',
+                    'subject_class' => 'policy',
+                    'subject_type_keys' => ['deviceConfiguration'],
+                    'filters' => [],
+                ],
+                [
+                    'domain_key' => 'entra',
+                    'subject_class' => 'control',
+                    'subject_type_keys' => ['conditionalAccessPolicy'],
+                    'filters' => [],
+                ],
+            ],
+        ],
+    ]);
+
+    $snapshot = BaselineSnapshot::factory()->create([
+        'workspace_id' => (int) $tenant->workspace_id,
+        'baseline_profile_id' => (int) $profile->getKey(),
+    ]);
+
+    $profile->update(['active_snapshot_id' => (int) $snapshot->getKey()]);
+
+    BaselineTenantAssignment::factory()->create([
+        'workspace_id' => (int) $tenant->workspace_id,
+        'tenant_id' => (int) $tenant->getKey(),
+        'baseline_profile_id' => (int) $profile->getKey(),
+    ]);
+
+    Livewire::test(BaselineCompareLanding::class)
+        ->callAction('compareNow')
+        ->assertNotified('Cannot start comparison')
+        ->assertStatus(200);
+
+    Queue::assertNotPushed(CompareBaselineToTenantJob::class);
+    expect(OperationRun::query()->where('type', 'baseline_compare')->count())->toBe(0);
+});
+
 it('can refresh stats without calling mount directly', function (): void {
     [$user, $tenant] = createUserWithTenant(role: 'owner');
     $this->actingAs($user);

apps/platform/tests/Feature/Filament/BaselineCompareLandingWhyNoFindingsTest.php

@@ -182,3 +182,75 @@
         ->assertDontSee('Evidence gap details')
         ->assertSee('Baseline compare evidence');
 });
+
+it('includes strategy diagnostics in the landing evidence payload when strategy-owned compare processing fails', function (): void {
+    [$user, $tenant] = createUserWithTenant(role: 'owner');
+    $this->actingAs($user);
+
+    $tenant->makeCurrent();
+    Filament::setTenant($tenant, true);
+
+    $profile = BaselineProfile::factory()->active()->create([
+        'workspace_id' => (int) $tenant->workspace_id,
+    ]);
+
+    $snapshot = BaselineSnapshot::factory()->create([
+        'workspace_id' => (int) $tenant->workspace_id,
+        'baseline_profile_id' => (int) $profile->getKey(),
+    ]);
+
+    $profile->update(['active_snapshot_id' => (int) $snapshot->getKey()]);
+
+    BaselineTenantAssignment::factory()->create([
+        'workspace_id' => (int) $tenant->workspace_id,
+        'tenant_id' => (int) $tenant->getKey(),
+        'baseline_profile_id' => (int) $profile->getKey(),
+    ]);
+
+    OperationRun::factory()->create([
+        'tenant_id' => (int) $tenant->getKey(),
+        'workspace_id' => (int) $tenant->workspace_id,
+        'type' => OperationRunType::BaselineCompare->value,
+        'status' => OperationRunStatus::Completed->value,
+        'outcome' => OperationRunOutcome::PartiallySucceeded->value,
+        'completed_at' => now(),
+        'context' => [
+            'baseline_profile_id' => (int) $profile->getKey(),
+            'baseline_snapshot_id' => (int) $snapshot->getKey(),
+            'baseline_compare' => [
+                'reason_code' => BaselineCompareReasonCode::StrategyFailed->value,
+                'coverage' => [
+                    'effective_types' => ['deviceConfiguration'],
+                    'covered_types' => ['deviceConfiguration'],
+                    'uncovered_types' => [],
+                    'proof' => true,
+                ],
+                'fidelity' => 'meta',
+                'strategy' => [
+                    'key' => 'intune_policy',
+                    'selection_state' => 'supported',
+                    'operator_reason' => 'Compare strategy resolved successfully.',
+                    'execution_diagnostics' => [
+                        'failed' => true,
+                        'exception_class' => RuntimeException::class,
+                    ],
+                    'state_counts' => [
+                        'failed' => 1,
+                    ],
+                ],
+                'evidence_gaps' => [
+                    'count' => 1,
+                    'by_reason' => [
+                        'strategy_failed' => 1,
+                    ],
+                ],
+            ],
+        ],
+    ]);
+
+    Livewire::test(BaselineCompareLanding::class)
+        ->assertSee('Baseline compare evidence')
+        ->assertSee('intune_policy')
+        ->assertSee('strategy_failed')
+        ->assertSee('RuntimeException');
+});

apps/platform/tests/Feature/Filament/BaselineCompareMatrixPageTest.php

@@ -2,12 +2,20 @@
 
 declare(strict_types=1);
 
+require_once dirname(__DIR__).'/Baselines/Support/FakeCompareStrategy.php';
+
 use App\Filament\Pages\BaselineCompareMatrix;
 use App\Filament\Resources\BaselineProfileResource;
 use App\Models\User;
 use App\Models\WorkspaceMembership;
+use App\Support\Baselines\Compare\CompareStrategyRegistry;
+use App\Support\Baselines\Compare\IntuneCompareStrategy;
+use App\Support\Governance\GovernanceSubjectTaxonomyRegistry;
+use Filament\Actions\Action;
 use Illuminate\Foundation\Testing\RefreshDatabase;
 use Livewire\Livewire;
+use Tests\Feature\Baselines\Support\FakeCompareStrategy;
+use Tests\Feature\Baselines\Support\FakeGovernanceSubjectTaxonomyRegistry;
 use Tests\Feature\Concerns\BuildsBaselineCompareMatrixFixtures;
 
 uses(RefreshDatabase::class, BuildsBaselineCompareMatrixFixtures::class);
@@ -199,6 +207,44 @@
         ->assertSee('Capture a complete baseline snapshot before using the compare matrix.');
 });
 
+it('disables compare-assigned-tenants when the scope spans multiple compare strategy families', function (): void {
+    $fixture = $this->makeBaselineCompareMatrixFixture();
+
+    app()->instance(GovernanceSubjectTaxonomyRegistry::class, new FakeGovernanceSubjectTaxonomyRegistry);
+    app()->instance(CompareStrategyRegistry::class, new CompareStrategyRegistry([
+        app(IntuneCompareStrategy::class),
+        app(FakeCompareStrategy::class),
+    ]));
+
+    $fixture['profile']->update([
+        'scope_jsonb' => [
+            'version' => 2,
+            'entries' => [
+                [
+                    'domain_key' => 'intune',
+                    'subject_class' => 'policy',
+                    'subject_type_keys' => ['deviceConfiguration'],
+                    'filters' => [],
+                ],
+                [
+                    'domain_key' => 'entra',
+                    'subject_class' => 'control',
+                    'subject_type_keys' => ['conditionalAccessPolicy'],
+                    'filters' => [],
+                ],
+            ],
+        ],
+    ]);
+
+    $this->setAdminWorkspaceContext($fixture['user'], $fixture['workspace']);
+
+    Livewire::actingAs($fixture['user'])
+        ->test(BaselineCompareMatrix::class, ['record' => $fixture['profile']->getKey()])
+        ->assertActionVisible('compareAssignedTenants')
+        ->assertActionDisabled('compareAssignedTenants')
+        ->assertActionExists('compareAssignedTenants', fn (Action $action): bool => $action->getTooltip() === 'The selected governed subjects span multiple compare strategy families and must be narrowed before comparing assigned tenants.');
+});
+
 it('renders an empty state when the baseline profile has no assigned tenants', function (): void {
     $fixture = $this->makeBaselineCompareMatrixFixture();
 

apps/platform/tests/Feature/Filament/BaselineProfileCompareStartSurfaceTest.php

@@ -1,5 +1,7 @@
 <?php
 
+require_once dirname(__DIR__).'/Baselines/Support/FakeCompareStrategy.php';
+
 use App\Filament\Resources\BaselineProfileResource;
 use App\Filament\Resources\BaselineProfileResource\Pages\ViewBaselineProfile;
 use App\Jobs\CompareBaselineToTenantJob;
@@ -8,6 +10,9 @@
 use App\Models\BaselineTenantAssignment;
 use App\Models\OperationRun;
 use App\Support\Baselines\BaselineCaptureMode;
+use App\Support\Baselines\Compare\CompareStrategyRegistry;
+use App\Support\Baselines\Compare\IntuneCompareStrategy;
+use App\Support\Governance\GovernanceSubjectTaxonomyRegistry;
 use App\Support\Workspaces\WorkspaceContext;
 use Filament\Actions\Action;
 use Filament\Actions\ActionGroup;
@@ -15,6 +20,8 @@
 use Illuminate\Support\Facades\Queue;
 use Livewire\Features\SupportTesting\Testable;
 use Livewire\Livewire;
+use Tests\Feature\Baselines\Support\FakeCompareStrategy;
+use Tests\Feature\Baselines\Support\FakeGovernanceSubjectTaxonomyRegistry;
 
 function baselineProfileHeaderActions(Testable $component): array
 {
@@ -149,6 +156,64 @@ function baselineProfileHeaderActions(Testable $component): array
     expect(OperationRun::query()->where('type', 'baseline_compare')->count())->toBe(0);
 });
 
+it('shows mixed-strategy compare rejection truth on the workspace start surface', function (): void {
+    Queue::fake();
+
+    [$user, $tenant] = createUserWithTenant(role: 'owner');
+
+    app()->instance(GovernanceSubjectTaxonomyRegistry::class, new FakeGovernanceSubjectTaxonomyRegistry);
+    app()->instance(CompareStrategyRegistry::class, new CompareStrategyRegistry([
+        app(IntuneCompareStrategy::class),
+        app(FakeCompareStrategy::class),
+    ]));
+
+    $profile = BaselineProfile::factory()->active()->create([
+        'workspace_id' => (int) $tenant->workspace_id,
+        'scope_jsonb' => [
+            'version' => 2,
+            'entries' => [
+                [
+                    'domain_key' => 'intune',
+                    'subject_class' => 'policy',
+                    'subject_type_keys' => ['deviceConfiguration'],
+                    'filters' => [],
+                ],
+                [
+                    'domain_key' => 'entra',
+                    'subject_class' => 'control',
+                    'subject_type_keys' => ['conditionalAccessPolicy'],
+                    'filters' => [],
+                ],
+            ],
+        ],
+    ]);
+
+    $snapshot = BaselineSnapshot::factory()->create([
+        'workspace_id' => (int) $tenant->workspace_id,
+        'baseline_profile_id' => (int) $profile->getKey(),
+    ]);
+
+    $profile->update(['active_snapshot_id' => (int) $snapshot->getKey()]);
+
+    BaselineTenantAssignment::factory()->create([
+        'workspace_id' => (int) $tenant->workspace_id,
+        'tenant_id' => (int) $tenant->getKey(),
+        'baseline_profile_id' => (int) $profile->getKey(),
+    ]);
+
+    session()->put(WorkspaceContext::SESSION_KEY, (int) $tenant->workspace_id);
+
+    Livewire::actingAs($user)
+        ->test(ViewBaselineProfile::class, ['record' => $profile->getKey()])
+        ->assertSee('Mixed strategy scope')
+        ->callAction('compareNow', data: ['target_tenant_id' => (int) $tenant->getKey()])
+        ->assertNotified('Cannot start comparison')
+        ->assertStatus(200);
+
+    Queue::assertNotPushed(CompareBaselineToTenantJob::class);
+    expect(OperationRun::query()->where('type', 'baseline_compare')->count())->toBe(0);
+});
+
 it('moves compare-matrix navigation into related context while keeping compare-assigned-tenants secondary', function (): void {
     [$user, $tenant] = createUserWithTenant(role: 'owner');
     $this->actingAs($user);

apps/platform/tests/Feature/Filament/BaselineSnapshotDegradedStateTest.php

@@ -48,7 +48,7 @@
     $this->actingAs($user)
         ->get(BaselineSnapshotResource::getUrl('view', ['record' => $snapshot], panel: 'admin'))
         ->assertOk()
-        ->assertSeeInOrder(['Artifact truth', 'Coverage summary', 'Captured policy types', 'Technical detail'])
+        ->assertSeeInOrder(['Artifact truth', 'Coverage summary', 'Captured governed subjects', 'Technical detail'])
         ->assertSee('Reference only')
         ->assertSee('Inventory metadata')
         ->assertSee('Metadata-only evidence was captured for this item.')
@@ -111,7 +111,7 @@ public function render(BaselineSnapshotItem $item): RenderedSnapshotItem
         ->get(BaselineSnapshotResource::getUrl('view', ['record' => $snapshot], panel: 'admin'))
         ->assertOk()
         ->assertSee('Technical detail')
-        ->assertSee('Structured rendering failed for this policy type. Fallback metadata is shown instead.')
+        ->assertSee('Structured rendering failed for this governed subject family. Fallback metadata is shown instead.')
         ->assertSee('Bitlocker Require')
         ->assertSee('A fallback renderer is being used for this item.');
 });

apps/platform/tests/Feature/Filament/BaselineSnapshotStructuredRenderingTest.php

@@ -8,7 +8,7 @@
 use App\Models\BaselineSnapshot;
 use App\Models\BaselineSnapshotItem;
 
-it('renders the baseline snapshot detail page as summary-first with grouped policy browsing', function (): void {
+it('renders the baseline snapshot detail page as summary-first with grouped governed-subject browsing', function (): void {
     [$user, $tenant] = createUserWithTenant(role: 'readonly');
 
     $profile = BaselineProfile::factory()->active()->create([
@@ -93,13 +93,14 @@
         ->assertSee('Capture timing')
         ->assertSee('Related context')
         ->assertSee(BaselineProfileResource::getUrl('view', ['record' => $profile], panel: 'admin'), false)
-        ->assertSeeInOrder(['Security Baseline', 'Coverage summary', 'Captured policy types', 'Technical detail'])
+        ->assertSeeInOrder(['Security Baseline', 'Coverage summary', 'Captured governed subjects', 'Technical detail'])
         ->assertSee('Security Reader')
         ->assertSee('Bitlocker Require')
         ->assertSee('Mystery Policy')
         ->assertSee('Intune RBAC Role Definition')
         ->assertSee('Device Compliance')
         ->assertSee('Mystery Policy Type')
+        ->assertSee('Governed subject')
         ->assertDontSee('Intune RBAC Role Definition References');
 
     $this->actingAs($user)

apps/platform/tests/Feature/Filament/EnterpriseDetailTemplateRegressionTest.php

@@ -77,7 +77,7 @@
 
     $this->get(BaselineSnapshotResource::getUrl('view', ['record' => $snapshot], panel: 'admin'))
         ->assertOk()
-        ->assertSeeInOrder(['Security Baseline', 'Captured policy types', 'Technical detail']);
+        ->assertSeeInOrder(['Security Baseline', 'Captured governed subjects', 'Technical detail']);
 
     $this->get(BackupSetResource::getUrl('view', ['record' => $backupSet], tenant: $tenant))
         ->assertOk()

apps/platform/tests/Feature/Filament/OperationRunBaselineTruthSurfaceTest.php

@@ -151,6 +151,73 @@ function visibleLivewireText(Testable $component): string
         ->and(mb_strpos($pageText, 'Decision'))->toBeLessThan(mb_strpos($pageText, 'Artifact truth details'));
 });
 
+it('shows strategy diagnostics and operator-safe failure meaning for strategy-owned compare failures', function (): void {
+    [$user, $tenant] = createUserWithTenant(role: 'owner');
+
+    $run = OperationRun::factory()->create([
+        'tenant_id' => (int) $tenant->getKey(),
+        'workspace_id' => (int) $tenant->workspace_id,
+        'type' => 'baseline_compare',
+        'status' => 'completed',
+        'outcome' => 'partially_succeeded',
+        'context' => [
+            'baseline_compare' => [
+                'reason_code' => BaselineCompareReasonCode::StrategyFailed->value,
+                'coverage' => [
+                    'proof' => true,
+                    'effective_types' => ['conditionalAccessPolicy'],
+                    'covered_types' => ['conditionalAccessPolicy'],
+                    'uncovered_types' => [],
+                ],
+                'evidence_gaps' => [
+                    'count' => 1,
+                    'by_reason' => [
+                        'strategy_failed' => 1,
+                    ],
+                ],
+                'strategy' => [
+                    'key' => 'intune_policy',
+                    'selection_state' => 'supported',
+                    'operator_reason' => 'Compare strategy resolved successfully.',
+                    'execution_diagnostics' => [
+                        'failed' => true,
+                        'exception_class' => RuntimeException::class,
+                    ],
+                    'state_counts' => [
+                        'failed' => 2,
+                    ],
+                ],
+            ],
+        ],
+        'summary_counts' => [
+            'total' => 0,
+            'processed' => 0,
+            'errors_recorded' => 1,
+        ],
+        'completed_at' => now(),
+    ]);
+
+    $truth = app(ArtifactTruthPresenter::class)->forOperationRun($run->fresh());
+    $explanation = $truth->operatorExplanation;
+
+    Filament::setTenant(null, true);
+    $this->withSession([WorkspaceContext::SESSION_KEY => (int) $tenant->workspace_id]);
+    session([WorkspaceContext::SESSION_KEY => (int) $tenant->workspace_id]);
+
+    Livewire::actingAs($user)
+        ->test(TenantlessOperationRunViewer::class, ['run' => $run])
+        ->assertSee($explanation?->headline ?? '')
+        ->assertSee($explanation?->nextActionText ?? '')
+        ->assertSee('Compare strategy')
+        ->assertSee('Intune Policy')
+        ->assertSee('Strategy selection')
+        ->assertSee('Supported')
+        ->assertSee('Strategy subject states')
+        ->assertSee('Failed 2')
+        ->assertSee('Baseline compare evidence')
+        ->assertSee('RuntimeException');
+});
+
 it('deduplicates repeated artifact truth explanation text for follow-up runs without a usable artifact', function (): void {
     [$user, $tenant] = createUserWithTenant(role: 'owner');
 

apps/platform/tests/Feature/Filament/OperationRunEnterpriseDetailPageTest.php

@@ -9,8 +9,10 @@
 use App\Models\Workspace;
 use App\Models\WorkspaceMembership;
 use App\Support\Inventory\InventoryCoverage as InventoryCoveragePayload;
+use App\Support\Operations\ExecutionDenialReasonCode;
 use App\Support\OperationRunOutcome;
 use App\Support\OperationRunStatus;
+use App\Support\ReasonTranslation\ReasonPresenter;
 use App\Support\Workspaces\WorkspaceContext;
 use Filament\Facades\Filament;
 use Illuminate\Testing\TestResponse;
@@ -303,6 +305,47 @@ function baselineCompareGapContext(array $overrides = []): array
         ->assertSee('Adapter reconciler');
 });
 
+it('renders explicit reason-owner and platform-family semantics for blocked runs', function (): void {
+    [$user, $tenant] = createUserWithTenant(role: 'owner');
+
+    Filament::setTenant(null, true);
+
+    $run = OperationRun::factory()->create([
+        'workspace_id' => (int) $tenant->workspace_id,
+        'tenant_id' => (int) $tenant->getKey(),
+        'type' => 'inventory_sync',
+        'status' => OperationRunStatus::Completed->value,
+        'outcome' => OperationRunOutcome::Blocked->value,
+        'context' => [
+            'reason_code' => ExecutionDenialReasonCode::MissingCapability->value,
+            'execution_legitimacy' => [
+                'reason_code' => ExecutionDenialReasonCode::MissingCapability->value,
+            ],
+        ],
+        'failure_summary' => [[
+            'code' => 'operation.blocked',
+            'reason_code' => ExecutionDenialReasonCode::MissingCapability->value,
+            'message' => 'Operation blocked because the initiating actor no longer has the required capability.',
+        ]],
+    ]);
+
+    $reasonSemantics = app(ReasonPresenter::class)->semantics(
+        app(ReasonPresenter::class)->forOperationRun($run, 'run_detail'),
+    );
+
+    expect($reasonSemantics)->not->toBeNull();
+
+    $this->actingAs($user)
+        ->withSession([WorkspaceContext::SESSION_KEY => (int) $tenant->workspace_id])
+        ->get(route('admin.operations.view', ['run' => (int) $run->getKey()]))
+        ->assertOk()
+        ->assertSee('Explanation semantics')
+        ->assertSee('Reason owner')
+        ->assertSee($reasonSemantics['owner_label'])
+        ->assertSee('Platform reason family')
+        ->assertSee($reasonSemantics['family_label']);
+});
+
 it('renders evidence gap details section for baseline compare runs with gap subjects', function (): void {
     [$user, $tenant] = createUserWithTenant(role: 'owner');
 
@@ -340,7 +383,7 @@ function baselineCompareGapContext(array $overrides = []): array
         ->assertSee('2 affected')
         ->assertSee('WiFi-Corp-Profile')
         ->assertSee('Deleted-Policy-ABC')
-        ->assertSee('Policy type')
+        ->assertSee('Governed subject')
         ->assertSee('Subject class')
         ->assertSee('Outcome')
         ->assertSee('Next action')

apps/platform/tests/Feature/Filament/OperationRunListFiltersTest.php

@@ -160,11 +160,49 @@ function operationRunFilterIndicatorLabels($component): array
 
     expect($filter)->not->toBeNull();
     expect($filter?->getOptions())->toBe([
-        'inventory_sync' => 'Inventory sync',
+        'inventory.sync' => 'Inventory sync',
         'policy.sync' => 'Policy sync',
     ]);
 });
 
+it('filters legacy and provider-prefixed inventory runs through one canonical operation selection', function (): void {
+    [$user, $tenant] = createUserWithTenant(role: 'owner');
+
+    $legacyRun = OperationRun::factory()->create([
+        'tenant_id' => (int) $tenant->getKey(),
+        'workspace_id' => (int) $tenant->workspace_id,
+        'type' => 'inventory_sync',
+        'status' => OperationRunStatus::Completed->value,
+        'outcome' => OperationRunOutcome::Succeeded->value,
+    ]);
+
+    $providerPrefixedRun = OperationRun::factory()->create([
+        'tenant_id' => (int) $tenant->getKey(),
+        'workspace_id' => (int) $tenant->workspace_id,
+        'type' => 'provider.inventory.sync',
+        'status' => OperationRunStatus::Completed->value,
+        'outcome' => OperationRunOutcome::Succeeded->value,
+    ]);
+
+    $otherRun = OperationRun::factory()->create([
+        'tenant_id' => (int) $tenant->getKey(),
+        'workspace_id' => (int) $tenant->workspace_id,
+        'type' => 'policy.sync',
+        'status' => OperationRunStatus::Completed->value,
+        'outcome' => OperationRunOutcome::Succeeded->value,
+    ]);
+
+    Filament::setTenant($tenant, true);
+    $this->withSession([WorkspaceContext::SESSION_KEY => (int) $tenant->workspace_id]);
+    session([WorkspaceContext::SESSION_KEY => (int) $tenant->workspace_id]);
+
+    Livewire::actingAs($user)
+        ->test(Operations::class)
+        ->filterTable('type', 'inventory.sync')
+        ->assertCanSeeTableRecords([$legacyRun, $providerPrefixedRun])
+        ->assertCanNotSeeTableRecords([$otherRun]);
+});
+
 it('clears tenant-sensitive persisted filters when the canonical tenant context changes', function (): void {
     $tenantA = Tenant::factory()->create();
     [$user, $tenantA] = createUserWithTenant(tenant: $tenantA, role: 'owner');

apps/platform/tests/Feature/Monitoring/OperationRunResolvedReferencePresentationTest.php

@@ -61,3 +61,21 @@
         ->assertSee('Back to Operations')
         ->assertDontSee('← Back to Archived Tenant');
 });
+
+it('resolves legacy operation values to canonical operation metadata on read paths', function (): void {
+    [$user, $tenant] = createUserWithTenant(role: 'owner');
+    $this->actingAs($user);
+
+    $run = OperationRun::factory()->for($tenant)->create([
+        'workspace_id' => (int) $tenant->workspace_id,
+        'type' => 'backup_schedule_run',
+    ]);
+
+    expect($run->canonicalOperationType())->toBe('backup.schedule.execute');
+
+    $this->withSession([WorkspaceContext::SESSION_KEY => (int) $tenant->workspace_id])
+        ->get(OperationRunLinks::tenantlessView($run))
+        ->assertOk()
+        ->assertSee('Backup schedule run')
+        ->assertDontSee('backup_schedule_run');
+});

apps/platform/tests/Feature/ReasonTranslation/ReasonTranslationExplanationTest.php

@@ -4,6 +4,7 @@
 
 use App\Support\Baselines\BaselineCompareReasonCode;
 use App\Support\Baselines\BaselineReasonCodes;
+use App\Support\Governance\PlatformVocabularyGlossary;
 use App\Support\ReasonTranslation\ReasonPresenter;
 use App\Support\Ui\OperatorExplanation\TrustworthinessLevel;
 
@@ -40,3 +41,15 @@
         'missing_input',
     ],
 ]);
+
+it('keeps governance reason ownership and family semantics explicit', function (): void {
+    $presenter = app(ReasonPresenter::class);
+    $semantics = $presenter->semantics(
+        $presenter->forArtifactTruth(BaselineCompareReasonCode::CoverageUnproven->value, 'artifact_truth'),
+    );
+
+    expect($semantics)->not->toBeNull()
+        ->and($semantics['owner_label'] ?? null)->toBe('Governance detail')
+        ->and($semantics['family_label'] ?? null)->toBe('Coverage')
+        ->and($semantics['boundary_classification'] ?? null)->toBe(PlatformVocabularyGlossary::BOUNDARY_CROSS_DOMAIN_GOVERNANCE);
+});

apps/platform/tests/Feature/ReviewPack/ReviewPackWidgetTest.php

@@ -11,6 +11,8 @@
 use App\Models\Tenant;
 use App\Services\Evidence\EvidenceSnapshotService;
 use App\Support\Evidence\EvidenceSnapshotStatus;
+use App\Support\Providers\ProviderReasonCodes;
+use App\Support\ReasonTranslation\ReasonPresenter;
 use Illuminate\Foundation\Testing\RefreshDatabase;
 use Illuminate\Support\Facades\Storage;
 use Livewire\Livewire;
@@ -184,6 +186,51 @@ function seedWidgetReviewPackSnapshot(Tenant $tenant): EvidenceSnapshot
         ->assertDontSee('wire:poll.10s', escape: false);
 });
 
+it('renders translated reason semantics for failed review-pack runs when available', function (): void {
+    $tenant = Tenant::factory()->create();
+    [$user, $tenant] = createUserWithTenant(tenant: $tenant, role: 'owner');
+
+    $run = OperationRun::factory()->create([
+        'tenant_id' => (int) $tenant->getKey(),
+        'workspace_id' => (int) $tenant->workspace_id,
+        'type' => 'tenant.review_pack.generate',
+        'status' => 'completed',
+        'outcome' => 'failed',
+        'context' => [
+            'reason_code' => ProviderReasonCodes::ProviderPermissionMissing,
+        ],
+        'failure_summary' => [[
+            'code' => 'operation.failed',
+            'reason_code' => ProviderReasonCodes::ProviderPermissionMissing,
+            'message' => 'The provider app is missing a required permission.',
+        ]],
+    ]);
+
+    ReviewPack::factory()->failed()->create([
+        'tenant_id' => (int) $tenant->getKey(),
+        'workspace_id' => (int) $tenant->workspace_id,
+        'initiated_by_user_id' => (int) $user->getKey(),
+        'operation_run_id' => (int) $run->getKey(),
+    ]);
+
+    $reasonSemantics = app(ReasonPresenter::class)->semantics(
+        app(ReasonPresenter::class)->forOperationRun($run, 'review_pack_widget'),
+    );
+    $reasonEnvelope = app(ReasonPresenter::class)->forOperationRun($run, 'review_pack_widget');
+
+    expect($reasonEnvelope)->not->toBeNull()
+        ->and($reasonSemantics)->not->toBeNull();
+
+    setTenantPanelContext($tenant);
+
+    Livewire::actingAs($user)
+        ->test(TenantReviewPackCard::class, ['record' => $tenant])
+        ->assertSee($reasonEnvelope->operatorLabel)
+        ->assertSee($reasonEnvelope->shortExplanation)
+        ->assertSee($reasonSemantics['owner_label'])
+        ->assertSee($reasonSemantics['family_label']);
+});
+
 // ─── Expired State ───────────────────────────────────────────
 
 it('shows generate action for an expired pack', function (): void {

apps/platform/tests/Feature/TenantReview/TenantReviewExplanationSurfaceTest.php

@@ -5,6 +5,7 @@
 use App\Filament\Pages\Reviews\ReviewRegister;
 use App\Filament\Resources\TenantReviewResource;
 use App\Models\Tenant;
+use App\Support\ReasonTranslation\ReasonPresenter;
 use App\Support\Ui\GovernanceArtifactTruth\ArtifactTruthPresenter;
 use App\Support\Workspaces\WorkspaceContext;
 use Livewire\Livewire;
@@ -32,6 +33,9 @@
 
     $truth = app(ArtifactTruthPresenter::class)->forTenantReview($review);
     $explanation = $truth->operatorExplanation;
+    $reasonSemantics = app(ReasonPresenter::class)->semantics($truth->reason?->toReasonResolutionEnvelope());
+
+    expect($reasonSemantics)->not->toBeNull();
 
     setTenantPanelContext($tenant);
 
@@ -39,7 +43,11 @@
         ->get(TenantReviewResource::tenantScopedUrl('view', ['record' => $review], $tenant))
         ->assertOk()
         ->assertSee($explanation?->headline ?? '')
-        ->assertSee($explanation?->nextActionText ?? '');
+        ->assertSee($explanation?->nextActionText ?? '')
+        ->assertSee('Reason owner')
+        ->assertSee($reasonSemantics['owner_label'])
+        ->assertSee('Platform reason family')
+        ->assertSee($reasonSemantics['family_label']);
 
     setAdminPanelContext();
     session()->put(WorkspaceContext::SESSION_KEY, (int) $tenant->workspace_id);

apps/platform/tests/Unit/Baselines/CompareStrategyRegistryTest.php

@@ -0,0 +1,217 @@
+<?php
+
+declare(strict_types=1);
+
+use App\Models\Tenant;
+use App\Support\Baselines\BaselineScope;
+use App\Support\Baselines\Compare\CompareOrchestrationContext;
+use App\Support\Baselines\Compare\CompareStrategy;
+use App\Support\Baselines\Compare\CompareStrategyCapability;
+use App\Support\Baselines\Compare\CompareStrategyKey;
+use App\Support\Baselines\Compare\CompareStrategyRegistry;
+use App\Support\Governance\GovernanceDomainKey;
+use App\Support\Governance\GovernanceSubjectClass;
+
+it('selects a single compatible strategy family for a canonical scope entry', function (): void {
+    $registry = new CompareStrategyRegistry([
+        compareStrategyStub(
+            key: 'intune_policy',
+            capabilities: [
+                new CompareStrategyCapability(
+                    strategyKey: CompareStrategyKey::intunePolicy(),
+                    domainKeys: [GovernanceDomainKey::Intune->value, GovernanceDomainKey::PlatformFoundation->value],
+                    subjectClasses: [
+                        GovernanceSubjectClass::Policy->value,
+                        GovernanceSubjectClass::ConfigurationResource->value,
+                    ],
+                ),
+            ],
+        ),
+    ]);
+
+    $scope = BaselineScope::fromJsonb([
+        'version' => 2,
+        'entries' => [
+            [
+                'domain_key' => GovernanceDomainKey::Intune->value,
+                'subject_class' => GovernanceSubjectClass::Policy->value,
+                'subject_type_keys' => ['deviceConfiguration'],
+                'filters' => [],
+            ],
+            [
+                'domain_key' => GovernanceDomainKey::PlatformFoundation->value,
+                'subject_class' => GovernanceSubjectClass::ConfigurationResource->value,
+                'subject_type_keys' => ['assignmentFilter'],
+                'filters' => [],
+            ],
+        ],
+    ]);
+
+    $selection = $registry->select($scope);
+
+    expect($selection->isSupported())->toBeTrue()
+        ->and($selection->strategyKey?->value)->toBe('intune_policy')
+        ->and($selection->matchedScopeEntries)->toHaveCount(2)
+        ->and($selection->rejectedScopeEntries)->toBe([]);
+});
+
+it('rejects canonical scope entries when no strategy supports them', function (): void {
+    $registry = new CompareStrategyRegistry([
+        compareStrategyStub(
+            key: 'intune_policy',
+            capabilities: [
+                new CompareStrategyCapability(
+                    strategyKey: CompareStrategyKey::intunePolicy(),
+                    domainKeys: [GovernanceDomainKey::Intune->value],
+                    subjectClasses: [GovernanceSubjectClass::Policy->value],
+                ),
+            ],
+        ),
+    ]);
+
+    $scope = new BaselineScope(
+        entries: [[
+            'domain_key' => GovernanceDomainKey::Entra->value,
+            'subject_class' => GovernanceSubjectClass::Control->value,
+            'subject_type_keys' => ['conditionalAccessPolicy'],
+            'filters' => [],
+        ]],
+        version: 2,
+    );
+
+    $selection = $registry->select($scope);
+
+    expect($selection->isUnsupported())->toBeTrue()
+        ->and($selection->strategyKey)->toBeNull()
+        ->and($selection->matchedScopeEntries)->toBe([])
+        ->and($selection->rejectedScopeEntries)->toHaveCount(1);
+});
+
+it('marks scope as mixed when multiple strategy families are required', function (): void {
+    $registry = new CompareStrategyRegistry([
+        compareStrategyStub(
+            key: 'intune_policy',
+            capabilities: [
+                new CompareStrategyCapability(
+                    strategyKey: CompareStrategyKey::intunePolicy(),
+                    domainKeys: [GovernanceDomainKey::Intune->value],
+                    subjectClasses: [GovernanceSubjectClass::Policy->value],
+                ),
+            ],
+        ),
+        compareStrategyStub(
+            key: 'future_control',
+            capabilities: [
+                new CompareStrategyCapability(
+                    strategyKey: CompareStrategyKey::from('future_control'),
+                    domainKeys: [GovernanceDomainKey::Entra->value],
+                    subjectClasses: [GovernanceSubjectClass::Control->value],
+                ),
+            ],
+        ),
+    ]);
+
+    $scope = new BaselineScope(
+        entries: [
+            [
+                'domain_key' => GovernanceDomainKey::Intune->value,
+                'subject_class' => GovernanceSubjectClass::Policy->value,
+                'subject_type_keys' => ['deviceConfiguration'],
+                'filters' => [],
+            ],
+            [
+                'domain_key' => GovernanceDomainKey::Entra->value,
+                'subject_class' => GovernanceSubjectClass::Control->value,
+                'subject_type_keys' => ['conditionalAccessPolicy'],
+                'filters' => [],
+            ],
+        ],
+        version: 2,
+    );
+
+    $selection = $registry->select($scope);
+
+    expect($selection->isMixed())->toBeTrue()
+        ->and($selection->strategyKey)->toBeNull()
+        ->and($selection->matchedScopeEntries)->toHaveCount(2)
+        ->and($selection->diagnostics['matched_strategy_keys'] ?? [])->toEqual(['future_control', 'intune_policy']);
+});
+
+it('supports deterministic future-domain selection without implicit intune fallback', function (): void {
+    $registry = new CompareStrategyRegistry([
+        compareStrategyStub(
+            key: 'future_control',
+            capabilities: [
+                new CompareStrategyCapability(
+                    strategyKey: CompareStrategyKey::from('future_control'),
+                    domainKeys: [GovernanceDomainKey::Entra->value],
+                    subjectClasses: [GovernanceSubjectClass::Control->value],
+                ),
+            ],
+        ),
+    ]);
+
+    $scope = new BaselineScope(
+        entries: [[
+            'domain_key' => GovernanceDomainKey::Entra->value,
+            'subject_class' => GovernanceSubjectClass::Control->value,
+            'subject_type_keys' => ['conditionalAccessPolicy'],
+            'filters' => [],
+        ]],
+        version: 2,
+    );
+
+    $selection = $registry->select($scope);
+
+    expect($selection->isSupported())->toBeTrue()
+        ->and($selection->strategyKey?->value)->toBe('future_control')
+        ->and($registry->resolve('future_control'))->toBeInstanceOf(CompareStrategy::class);
+});
+
+it('throws when resolving an unknown strategy key', function (): void {
+    $registry = new CompareStrategyRegistry([]);
+
+    expect(fn (): CompareStrategy => $registry->resolve('missing_strategy'))
+        ->toThrow(InvalidArgumentException::class, 'Unknown compare strategy');
+});
+
+/**
+ * @param  list<CompareStrategyCapability>  $capabilities
+ */
+function compareStrategyStub(string $key, array $capabilities): CompareStrategy
+{
+    return new class($key, $capabilities) implements CompareStrategy
+    {
+        /**
+         * @param  list<CompareStrategyCapability>  $capabilities
+         */
+        public function __construct(
+            private readonly string $keyValue,
+            private readonly array $capabilities,
+        ) {}
+
+        public function key(): CompareStrategyKey
+        {
+            return CompareStrategyKey::from($this->keyValue);
+        }
+
+        public function capabilities(): array
+        {
+            return $this->capabilities;
+        }
+
+        public function compare(
+            CompareOrchestrationContext $context,
+            Tenant $tenant,
+            array $baselineItems,
+            array $currentItems,
+            array $resolvedCurrentEvidence,
+            array $severityMapping,
+        ): array {
+            return [
+                'subject_results' => [],
+                'diagnostics' => [],
+            ];
+        }
+    };
+}

apps/platform/tests/Unit/Baselines/CompareSubjectResultContractTest.php

@@ -0,0 +1,122 @@
+<?php
+
+declare(strict_types=1);
+
+use App\Support\Baselines\Compare\CompareFindingCandidate;
+use App\Support\Baselines\Compare\CompareState;
+use App\Support\Baselines\Compare\CompareSubjectIdentity;
+use App\Support\Baselines\Compare\CompareSubjectProjection;
+use App\Support\Baselines\Compare\CompareSubjectResult;
+
+it('serializes compare subject results with structured finding and diagnostics payloads', function (): void {
+    $result = new CompareSubjectResult(
+        subjectIdentity: new CompareSubjectIdentity(
+            domainKey: 'entra',
+            subjectClass: 'control',
+            subjectTypeKey: 'conditionalAccessPolicy',
+            externalSubjectId: 'cap-1',
+            subjectKey: 'cap-1',
+        ),
+        projection: new CompareSubjectProjection(
+            platformSubjectClass: 'control',
+            domainKey: 'entra',
+            subjectTypeKey: 'conditionalAccessPolicy',
+            operatorLabel: 'Conditional Access Policy',
+            summaryKind: 'control_snapshot',
+            additionalLabels: ['family' => 'identity'],
+        ),
+        baselineAvailability: 'available',
+        currentStateAvailability: 'available',
+        compareState: CompareState::Drift,
+        trustLevel: 'limited_confidence',
+        evidenceQuality: 'meta',
+        severityRecommendation: 'medium',
+        findingCandidate: new CompareFindingCandidate(
+            changeType: 'different_version',
+            severity: 'medium',
+            fingerprintBasis: [
+                'policy_type' => 'conditionalAccessPolicy',
+                'subject_key' => 'cap-1',
+                'change_type' => 'different_version',
+            ],
+            evidencePayload: [
+                'summary' => ['kind' => 'control_snapshot'],
+            ],
+        ),
+        diagnostics: [
+            'strategy_key' => 'future_control',
+        ],
+    );
+
+    $payload = $result->toArray();
+
+    expect($result->hasFindingCandidate())->toBeTrue()
+        ->and($result->isGapState())->toBeFalse()
+        ->and($payload['compare_state'])->toBe(CompareState::Drift->value)
+        ->and($payload['baseline_availability'])->toBe('available')
+        ->and($payload['current_state_availability'])->toBe('available')
+        ->and($payload['projection']['platform_subject_class'])->toBe('control')
+        ->and($payload['projection']['summary_kind'])->toBe('control_snapshot')
+        ->and($payload['finding_candidate']['change_type'])->toBe('different_version')
+        ->and($payload['finding_candidate']['severity'])->toBe('medium')
+        ->and($payload['diagnostics']['strategy_key'])->toBe('future_control');
+});
+
+it('requires a finding candidate for drift results', function (): void {
+    expect(fn (): CompareSubjectResult => new CompareSubjectResult(
+        subjectIdentity: new CompareSubjectIdentity('intune', 'policy', 'deviceConfiguration', 'policy-1', 'policy-1'),
+        projection: new CompareSubjectProjection('policy', 'intune', 'deviceConfiguration', 'Policy 1'),
+        baselineAvailability: 'available',
+        currentStateAvailability: 'missing',
+        compareState: CompareState::Drift,
+        trustLevel: 'limited_confidence',
+        evidenceQuality: 'meta',
+    ))->toThrow(InvalidArgumentException::class, 'require a finding candidate');
+});
+
+it('rejects non-drift results that still try to write findings', function (): void {
+    expect(fn (): CompareSubjectResult => new CompareSubjectResult(
+        subjectIdentity: new CompareSubjectIdentity('entra', 'control', 'conditionalAccessPolicy', 'cap-1', 'cap-1'),
+        projection: new CompareSubjectProjection('control', 'entra', 'conditionalAccessPolicy', 'CAP 1'),
+        baselineAvailability: 'available',
+        currentStateAvailability: 'unknown',
+        compareState: CompareState::Incomplete,
+        trustLevel: 'unusable',
+        evidenceQuality: 'missing',
+        findingCandidate: new CompareFindingCandidate(
+            changeType: 'different_version',
+            severity: 'high',
+            fingerprintBasis: ['subject_key' => 'cap-1'],
+            evidencePayload: [],
+        ),
+    ))->toThrow(InvalidArgumentException::class, 'Only drift compare subject results');
+});
+
+it('treats unsupported, incomplete, ambiguous, and failed states as gap states', function (): void {
+    $states = [
+        CompareState::Unsupported,
+        CompareState::Incomplete,
+        CompareState::Ambiguous,
+        CompareState::Failed,
+    ];
+
+    foreach ($states as $state) {
+        $result = new CompareSubjectResult(
+            subjectIdentity: new CompareSubjectIdentity('entra', 'control', 'conditionalAccessPolicy', 'cap-1', 'cap-1'),
+            projection: new CompareSubjectProjection('control', 'entra', 'conditionalAccessPolicy', 'CAP 1'),
+            baselineAvailability: 'available',
+            currentStateAvailability: 'unknown',
+            compareState: $state,
+            trustLevel: 'unusable',
+            evidenceQuality: 'missing',
+            diagnostics: [
+                'reason_code' => 'strategy_failed',
+                'gap_record' => ['reason_code' => 'strategy_failed'],
+            ],
+        );
+
+        expect($result->isGapState())->toBeTrue()
+            ->and($result->gapReasonCode())->toBe('strategy_failed')
+            ->and($result->gapRecord())->toBe(['reason_code' => 'strategy_failed']);
+    }
+});

apps/platform/tests/Unit/Baselines/GovernanceSubjectTaxonomyRegistryTest.php

@@ -42,4 +42,12 @@
         ->and(collect($registry->active())->contains(
             static fn ($subjectType): bool => $subjectType->domainKey === GovernanceDomainKey::Entra,
         ))->toBeFalse();
+});
+
+it('finds subject types by subject key across legacy buckets and exposes contributor ownership metadata', function (): void {
+    $registry = app(GovernanceSubjectTaxonomyRegistry::class);
+
+    expect($registry->findBySubjectTypeKey('deviceConfiguration')?->domainKey)->toBe(GovernanceDomainKey::Intune)
+        ->and($registry->findBySubjectTypeKey('assignmentFilter', 'foundation_types')?->subjectClass)->toBe(GovernanceSubjectClass::ConfigurationResource)
+        ->and($registry->ownershipDescriptor()->canonicalNouns)->toBe(['domain_key', 'subject_class', 'subject_type_key', 'subject_type_label']);
 });

apps/platform/tests/Unit/Baselines/SnapshotRendering/BaselineSnapshotPresenterTest.php

@@ -108,6 +108,7 @@
         ->and(data_get($rendered, 'snapshot.overallFidelity'))->toBe('partial')
         ->and(data_get($rendered, 'snapshot.overallGapCount'))->toBe(1)
         ->and($rendered['summaryRows'])->toHaveCount(3)
+        ->and(data_get($rendered, 'summaryRows.0.subjectDescriptor.platform_noun'))->toBe('Governed subject')
         ->and(collect($rendered['groups'])->pluck('label')->all())
         ->toContain('Intune RBAC Role Definition', 'Device Compliance', 'Mystery Policy Type')
         ->and(data_get($rendered, 'technicalDetail.defaultCollapsed'))->toBeTrue();

apps/platform/tests/Unit/Support/Governance/PlatformSubjectDescriptorNormalizerTest.php

@@ -0,0 +1,45 @@
+<?php
+
+declare(strict_types=1);
+
+use App\Support\Governance\GovernanceDomainKey;
+use App\Support\Governance\GovernanceSubjectClass;
+use App\Support\Governance\PlatformSubjectDescriptorNormalizer;
+
+it('normalizes legacy policy_type payloads into governed-subject descriptors', function (): void {
+    $result = app(PlatformSubjectDescriptorNormalizer::class)->fromArray([
+        'policy_type' => 'deviceConfiguration',
+    ], 'baseline_compare');
+
+    expect($result->usedLegacyAlias)->toBeTrue()
+        ->and($result->descriptor->domainKey)->toBe(GovernanceDomainKey::Intune->value)
+        ->and($result->descriptor->subjectClass)->toBe(GovernanceSubjectClass::Policy->value)
+        ->and($result->descriptor->subjectTypeKey)->toBe('deviceConfiguration')
+        ->and($result->descriptor->platformNoun)->toBe('Governed subject');
+});
+
+it('builds governed-subject descriptors for canonical baseline scope entries', function (): void {
+    $descriptors = app(PlatformSubjectDescriptorNormalizer::class)->descriptorsForScopeEntries([
+        [
+            'domain_key' => GovernanceDomainKey::PlatformFoundation->value,
+            'subject_class' => GovernanceSubjectClass::ConfigurationResource->value,
+            'subject_type_keys' => ['assignmentFilter'],
+            'filters' => [],
+        ],
+    ]);
+
+    expect($descriptors)->toHaveCount(1)
+        ->and(data_get($descriptors, '0.descriptor.subject_type_key'))->toBe('assignmentFilter')
+        ->and(data_get($descriptors, '0.descriptor.domain_key'))->toBe(GovernanceDomainKey::PlatformFoundation->value)
+        ->and(data_get($descriptors, '0.source_surface'))->toBe('baseline_scope');
+});
+
+it('falls back to compatibility-only descriptors for unknown subject types', function (): void {
+    $result = app(PlatformSubjectDescriptorNormalizer::class)->fromArray([
+        'policy_type' => 'mysterySubject',
+    ], 'snapshot');
+
+    expect($result->usedLegacyAlias)->toBeTrue()
+        ->and($result->descriptor->subjectTypeKey)->toBe('mysterySubject')
+        ->and($result->warnings)->not->toBeEmpty();
+});

apps/platform/tests/Unit/Support/Governance/PlatformVocabularyGlossaryTest.php

@@ -0,0 +1,38 @@
+<?php
+
+declare(strict_types=1);
+
+use App\Support\Governance\PlatformVocabularyGlossary;
+
+it('publishes canonical term inventory with boundary classifications and retirement metadata', function (): void {
+    $glossary = app(PlatformVocabularyGlossary::class);
+
+    expect($glossary->canonicalTerms())
+        ->toContain('governed_subject', 'operation_type', 'policy_type')
+        ->and($glossary->term('governed_subject')?->boundaryClassification)->toBe(PlatformVocabularyGlossary::BOUNDARY_PLATFORM_CORE)
+        ->and($glossary->term('governed_subject')?->legacyAliases)->toContain('policy_type')
+        ->and($glossary->term('governed_subject')?->aliasRetirementPath)->toContain('policy_type');
+});
+
+it('prefers exact Intune-specific terms while still resolving platform aliases by context', function (): void {
+    $glossary = app(PlatformVocabularyGlossary::class);
+
+    expect($glossary->term('policy_type')?->boundaryClassification)->toBe(PlatformVocabularyGlossary::BOUNDARY_INTUNE_SPECIFIC)
+        ->and($glossary->resolveAlias('policy_type', 'compare')?->termKey)->toBe('governed_subject')
+        ->and($glossary->resolveAlias('policy_type', 'intune_adapter'))->toBeNull();
+});
+
+it('publishes contributor-facing registry, alias, and reason-namespace inventories', function (): void {
+    $glossary = app(PlatformVocabularyGlossary::class);
+    $termInventory = $glossary->termInventory();
+    $aliasInventory = $glossary->aliasRetirementInventory();
+    $registryInventory = $glossary->registryInventory();
+    $reasonNamespaceInventory = $glossary->reasonNamespaceInventory();
+
+    expect($termInventory['operation_type']['boundary_classification'] ?? null)->toBe(PlatformVocabularyGlossary::BOUNDARY_PLATFORM_CORE)
+        ->and($aliasInventory['governed_subject']['canonical_name'] ?? null)->toBe('governed_subject')
+        ->and($aliasInventory['governed_subject']['legacy_aliases'] ?? [])->toContain('policy_type')
+        ->and($registryInventory['operation_catalog']['canonical_nouns'] ?? [])->toContain('operation_type')
+        ->and($reasonNamespaceInventory['governance.baseline_compare']['boundary_classification'] ?? null)->toBe(PlatformVocabularyGlossary::BOUNDARY_CROSS_DOMAIN_GOVERNANCE)
+        ->and($reasonNamespaceInventory['rbac.intune']['boundary_classification'] ?? null)->toBe(PlatformVocabularyGlossary::BOUNDARY_INTUNE_SPECIFIC);
+});