Fix auth mock in tests

Add missing /api/v1/auth/status mock to MSW handlers to prevent
network errors during frontend tests

frontend/src/__tests__/mocks/handlers.ts

@@ -269,6 +269,17 @@ export const handlers = [
     return HttpResponse.json(body);
   }),
 
+  // ========================================================================
+  // Auth
+  // ========================================================================
+
+  http.get('/api/v1/auth/status', () => {
+    return HttpResponse.json({
+      auth_enabled: false,
+      requires_setup: false,
+    });
+  }),
+
   // ========================================================================
   // Version / Health
   // ========================================================================