feat(directory) : migrate Client into Directory module (back)

LST-58 (2.4), part 1/2 — Client move. Prospect + repertoire front are pending
the product spec and will be added on this branch afterward.

- Client entity moved to src/Module/Directory/Domain/Entity; repository split
  into Domain/Repository/ClientRepositoryInterface + Doctrine impl (bound in
  services.yaml). 5 client MCP tools moved to Infrastructure/Mcp/Tool, now
  injecting the interface.
- resolve_target_entities ClientInterface repointed to Directory\Client;
  Directory mapping added; DirectoryModule registered (id directory, 2 RBAC
  perms). Client.projects relation now uses ProjectInterface -> Directory no
  longer depends on ProjectManagement.
- ProjectManagement Create/UpdateProjectTool inject Directory's
  ClientRepositoryInterface; Serializer and fixtures repointed.
- Garde-fous: #[Auditable] + Timestampable/Blamable on Client (additive
  migration: created_at/updated_at + created_by/updated_by FK ON DELETE SET
  NULL + COMMENT).

161 tests green, mapping valid, no API route regression, cs-fixer clean.

src/Module/Directory/DirectoryModule.php

@@ -0,0 +1,41 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Module\Directory;
+
+use App\Shared\Domain\Module\ModuleInterface;
+
+final class DirectoryModule implements ModuleInterface
+{
+    public static function id(): string
+    {
+        return 'directory';
+    }
+
+    public static function label(): string
+    {
+        return 'Répertoire';
+    }
+
+    public static function isRequired(): bool
+    {
+        return false;
+    }
+
+    /**
+     * Permissions RBAC fin du Module Directory.
+     *
+     * Additif : alimente le catalogue RBAC. La sécurité des opérations API
+     * reste en ROLE_USER/ROLE_ADMIN (non recâblée ici).
+     *
+     * @return list<array{code: string, label: string}>
+     */
+    public static function permissions(): array
+    {
+        return [
+            ['code' => 'directory.clients.view', 'label' => 'Voir les clients'],
+            ['code' => 'directory.clients.manage', 'label' => 'Gérer les clients'],
+        ];
+    }
+}