## Summary
- replace the legacy Tenant and TenantMembership core models with ManagedEnvironment and ManagedEnvironmentMembership
- propagate the managed environment naming and key changes across Filament resources, pages, controllers, jobs, models, and supporting runtime paths
- add feature 279 spec artifacts and focused managed-environment test coverage for model behavior, route binding, panel context, authorization, and legacy guardrails
## Validation
- `cd apps/platform && ./vendor/bin/sail artisan test --compact tests/Feature/ManagedEnvironment/LegacyTenantCoreGuardTest.php tests/Feature/ManagedEnvironment/ManagedEnvironmentAuthorizationTest.php tests/Feature/ManagedEnvironment/ManagedEnvironmentPanelContextTest.php tests/Feature/ManagedEnvironment/ManagedEnvironmentRouteBindingTest.php tests/Unit/ManagedEnvironment/ManagedEnvironmentContextResolverTest.php tests/Unit/ManagedEnvironment/ManagedEnvironmentModelTest.php`
- `cd apps/platform && ./vendor/bin/sail bin pint --dirty --format agent`
## Notes
- branch pushed from commit `1123b122`
- browser smoke test file was added but not run in this pass
Co-authored-by: Ahmed Darrazi <ahmed.darrazi@live.de>
Reviewed-on: #335
