Add chatId in ws connection

README.md

@@ -66,10 +66,14 @@ Optional input audio filtering can be enabled through `audio_filter`. See
 Product endpoint:
 
 ```text
-ws://localhost:8000/ws-product
+ws://localhost:8000/ws-product?chatId=customer-chat-001
 ```
 
 This endpoint uses a stable JSON/base64 protocol named `va.ws.v1`. It is meant for browser, mobile, or other product applications that should not depend on Pipecat's internal protobuf frame schema.
+For FastGPT sessions, pass `chatId` on the websocket URL. The engine uses
+that id for FastGPT server-side memory; if the id has existing FastGPT
+records, the assistant greets with `欢迎回来继续对话`, otherwise it uses the
+FastGPT app opener.
 
 Start a session:
 
@@ -77,6 +81,7 @@ Start a session:
 {
   "type": "session.start",
   "protocol": "va.ws.v1",
+  "chatId": "customer-chat-001",
   "audio": {
     "encoding": "pcm_s16le",
     "sample_rate": 16000,