{"version":1,"transport":"WebSocket 文本帧，UTF-8 JSON","binary_encoding":"base64（字段名以 _b64 结尾）","server_to_client":["welcome","http_request","ping","cancel","broadcast","error"],"client_to_server":["hello","http_response","pong","event","error"],"reserved_types":["http_request_end","http_request_stream","http_response_chunk","http_response_end","http_response_start","tunnel_ack","tunnel_register","ws_close","ws_frame","ws_open"],"flow":["1. 客户端连接 wss://<domain>/private/ws/<key>，服务端校验 key","2. 服务端发送 welcome，客户端可回 hello","3. HTTP 请求到达 /private/<prefix>/<subpath> -> 生成 id 并登记到等待表(带超时定时器)","4. 服务端把 http_request 广播给全部 WS 客户端","5. 第一个返回该 id 的 http_response 胜出 -> 回写 HTTP 响应，删除表项与定时器","6. 定时器先到时 -> 回 504 服务已断开；无客户端在线 -> 直接回 503 服务已断开"]}