refactor(admin): migrate page titles from static map to self-registering pages

src/features/admin/pages/DashboardPage.client.js

@@ -1,6 +1,6 @@
 'use client';
 
-import { getWidgets } from '../registry.js';
+import { getWidgets, registerPage } from '../registry.js';
 import AdminHeader from '../components/AdminHeader.js';
 
 export default function DashboardPage({ stats }) {
@@ -18,3 +18,5 @@ export default function DashboardPage({ stats }) {
     </div>
   );
 }
+
+registerPage({ slug: 'dashboard', title: 'Tableau de bord', Component: DashboardPage });