feat: module architecture improvements — session keys, dependency graph, event dispatcher, deactivation hooks

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>

modules/addressbook/lib/Module/AddressBook/AddressBookAuthorizationPolicy.php

@@ -15,6 +15,7 @@ use MintyPHP\Service\Access\PermissionService;
 final class AddressBookAuthorizationPolicy implements AuthorizationPolicyInterface
 {
     public const ABILITY_VIEW = 'addressbook.view';
+    public const PERMISSION_KEY = 'address_book.view';
 
     public function __construct(
         private readonly PermissionService $permissionService
@@ -33,7 +34,7 @@ final class AddressBookAuthorizationPolicy implements AuthorizationPolicyInterfa
             return AuthorizationDecision::deny(403, 'forbidden');
         }
 
-        if (!$this->permissionService->userHas($actorUserId, PermissionService::ADDRESS_BOOK_VIEW)) {
+        if (!$this->permissionService->userHas($actorUserId, self::PERMISSION_KEY)) {
             return AuthorizationDecision::deny(403, 'forbidden');
         }