feat: return a scim error on unknown paths

appinfo/routes.php

@@ -17,5 +17,7 @@ return [
 		['name' => 'group#create', 'url' => '/Groups', 'verb' => 'POST'],
 		['name' => 'group#update', 'url' => '/Groups/{id}', 'verb' => 'PUT'],
 		['name' => 'group#destroy', 'url' => '/Groups/{id}', 'verb' => 'DELETE'],
+
+		['name' => 'catch_all#index', 'url' => '/{path}', 'verb' => 'GET'],
 	]
 ];

lib/Controller/CatchAllController.php

@@ -0,0 +1,22 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OCA\SCIMServiceProvider\Controller;
+
+use Exception;
+use OCA\SCIMServiceProvider\Responses\SCIMJSONResponse;
+use OCA\SCIMServiceProvider\Responses\SCIMListResponse;
+use OCP\AppFramework\ApiController;
+
+class CatchAllController extends ApiController {
+	/**
+	 * @NoCSRFRequired
+	 * @PublicPage
+	 *
+	 * @return SCIMListResponse
+	 */
+	public function index(string $path): SCIMJSONResponse {
+		throw new Exception('Not found', 404);
+	}
+}