Add Paramètres page: consolidate maintenance + account settings

public/admin/actions/maintenance.php

@@ -24,5 +24,10 @@ if ($action === 'enable_maintenance') {
     App::flash('error', "Action inconnue.");
 }
 
-header('Location: /admin/');
+$redirect = isset($_POST['redirect']) ? $_POST['redirect'] : '/admin/';
+// Allow only internal admin redirects for safety
+if (!preg_match('#^/admin/#', $redirect)) {
+    $redirect = '/admin/';
+}
+header('Location: ' . $redirect);
 exit();