feat: add Intune RBAC inventory and backup support (#155)
## Summary
- add Intune RBAC role definitions and role assignments as foundation-backed inventory, backup, and versioned snapshot types
- add RBAC-specific normalization, coverage, permission-warning handling, and preview-only restore safety behavior across existing Filament and service surfaces
- add spec 127 artifacts, contracts, audits, and focused regression coverage for inventory, backup, versioning, verification, and authorization behavior
## Testing
- `vendor/bin/sail bin pint --dirty --format agent`
- `vendor/bin/sail artisan test --compact tests/Feature/Inventory/InventorySyncServiceTest.php tests/Feature/Filament/InventoryCoverageTableTest.php tests/Feature/FoundationBackupTest.php tests/Feature/Filament/RestoreExecutionTest.php tests/Feature/RestoreUnknownPolicyTypeSafetyTest.php tests/Unit/GraphContractRegistryTest.php tests/Unit/FoundationSnapshotServiceTest.php tests/Feature/Verification/IntuneRbacPermissionCoverageTest.php tests/Unit/IntuneRoleDefinitionNormalizerTest.php tests/Unit/IntuneRoleAssignmentNormalizerTest.php`
## Notes
- tasks in `specs/127-rbac-inventory-backup/tasks.md` are complete except `T041`, which is the documented manual QA validation step
Co-authored-by: Ahmed Darrazi <ahmed.darrazi@live.de>
Reviewed-on: #155