fix(feishu): use thread_id as reply target when reply_to is empty

In Feishu topic groups (话题群), messages within a thread have a
thread_id but the reply_to field can be empty. The original code
only used reply_to for the reply API call, causing replies to
fall back to creating new top-level messages instead of replying
within the thread.

Now falls back to thread_id when reply_to is absent, ensuring
responses stay in the correct thread context.

Made-with: Cursor

gateway/platforms/feishu.py

@@ -3417,15 +3417,17 @@ class FeishuAdapter(BasePlatformAdapter):
         reply_to: Optional[str],
         metadata: Optional[Dict[str, Any]],
     ) -> Any:
-        reply_in_thread = bool((metadata or {}).get("thread_id"))
-        if reply_to:
+        thread_id = (metadata or {}).get("thread_id")
+        reply_in_thread = bool(thread_id)
+        effective_reply_to = reply_to or (thread_id if reply_in_thread else None)
+        if effective_reply_to:
             body = self._build_reply_message_body(
                 content=payload,
                 msg_type=msg_type,
                 reply_in_thread=reply_in_thread,
                 uuid_value=str(uuid.uuid4()),
             )
-            request = self._build_reply_message_request(reply_to, body)
+            request = self._build_reply_message_request(effective_reply_to, body)
             return await asyncio.to_thread(self._client.im.v1.message.reply, request)
 
         body = self._build_create_message_body(