Six targeted improvements to the modular monolith platform:
1. Fix AddressBook session key prefix to follow module.<id>.* convention
2. Move ADDRESS_BOOK_VIEW permission constant from core PermissionService into module
3. Add declarative JSON schema for module manifests (.agents/contracts/)
4. Add `requires` field with missing-dependency and circular-dependency detection
5. Add lightweight fire-and-forget event dispatcher (user.created/deleted/login/logout)
6. Add module deactivation hook interface and CLI script (bin/module-deactivate.php)
Includes 15 new architecture/unit tests covering all new functionality.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>