feat(modules): harden module platform with event constants, validation checks, and CLI improvements

- Add ModuleEvents constants class with all 8 event strings; update dispatch call sites
- ValidateCommand: check AuthorizationPolicy container registration (check 20)
- ValidateCommand: warn on unknown event_listeners keys (check 21)
- make:module --simple flag for minimal manifests
- module:deactivate reverse-dependency warning
- 12 new PHPUnit tests covering all improvements

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

core/App/Module/ModuleEvents.php

@@ -0,0 +1,42 @@
+<?php
+
+declare(strict_types=1);
+
+namespace MintyPHP\App\Module;
+
+/**
+ * Central registry of all module event names dispatched by core.
+ *
+ * Modules reference these constants in their event_listeners manifest declarations
+ * and in listener implementations. ValidateCommand warns on unknown event names.
+ */
+final class ModuleEvents
+{
+    public const USER_LOGIN = 'user.login';
+    public const USER_LOGOUT = 'user.logout';
+    public const USER_CREATED = 'user.created';
+    public const USER_DELETED = 'user.deleted';
+    public const USER_ACTIVATED = 'user.activated';
+    public const USER_DEACTIVATED = 'user.deactivated';
+    public const USER_ASSIGNMENT_CHANGED = 'user.assignment_changed';
+    public const SCHEDULER_JOB_FAILED = 'scheduler.job_failed';
+
+    /** @return list<string> */
+    public static function all(): array
+    {
+        return [
+            self::USER_LOGIN,
+            self::USER_LOGOUT,
+            self::USER_CREATED,
+            self::USER_DELETED,
+            self::USER_ACTIVATED,
+            self::USER_DEACTIVATED,
+            self::USER_ASSIGNMENT_CHANGED,
+            self::SCHEDULER_JOB_FAILED,
+        ];
+    }
+
+    private function __construct()
+    {
+    }
+}