feat: 对接生图功能

Co-authored-by: Copilot <copilot@github.com>

server/utils/createApiResponse.ts

@@ -71,3 +71,20 @@ export const createUpstreamErrorResponse = (
     errorData
   );
 };
+
+/** 判断上游或本地鉴权错误是否为 401，用于统一清理失效登录态 */
+export const isUnauthorizedError = (error: unknown): boolean => {
+  const fetchError = error as {
+    response?: {
+      status?: number;
+    };
+    status?: number;
+    statusCode?: number;
+  };
+
+  return (
+    fetchError.statusCode === 401 ||
+    fetchError.status === 401 ||
+    fetchError.response?.status === 401
+  );
+};