feat(discord): sync thread titles with session titles

agent/title_generator.py

@@ -152,7 +152,19 @@ def auto_title_session(
         return
 
     try:
-        session_db.set_session_title(session_id, title)
+        set_if_empty = getattr(session_db, "set_session_title_if_empty", None)
+        if callable(set_if_empty):
+            title_set = bool(set_if_empty(session_id, title))
+        else:
+            # Backward-compatible path for older/custom session stores. Re-check
+            # immediately before writing so user-set titles that landed during
+            # generation are less likely to be overwritten.
+            if session_db.get_session_title(session_id):
+                return
+            title_set = bool(session_db.set_session_title(session_id, title))
+        if not title_set:
+            logger.debug("Skipped auto-generated title because session title is no longer empty")
+            return
         logger.debug("Auto-generated session title: %s", title)
         if title_callback is not None:
             try:

gateway/platforms/base.py

@@ -2326,6 +2326,7 @@ def __init__(self, config: PlatformConfig, platform: Platform):
         self.config = config
         self.platform = platform
         self._message_handler: Optional[MessageHandler] = None
+        self._thread_title_handler: Optional[Callable[[Platform, str, str], Awaitable[None]]] = None
         # Optional hook (e.g. Telegram DM topic recovery) that rewrites
         # ``event.source.thread_id`` before session keying. Returns the
         # corrected thread_id or None to leave the source untouched.
@@ -2666,6 +2667,16 @@ def _should_auto_tts_for_chat(self, chat_id: str) -> bool:
     def set_fatal_error_handler(self, handler: Callable[["BasePlatformAdapter"], Awaitable[None] | None]) -> None:
         self._fatal_error_handler = handler
 
+    def set_thread_title_handler(self, handler: Optional[Callable[[Platform, str, str], Awaitable[None]]]) -> None:
+        """Set an optional handler for platform thread-title changes."""
+        self._thread_title_handler = handler
+
+    async def _notify_thread_title_change(self, thread_id: str, title: str) -> None:
+        handler = self._thread_title_handler
+        if not handler or not thread_id or not title:
+            return
+        await handler(self.platform, str(thread_id), str(title))
+
     def _mark_connected(self) -> None:
         self._running = True
         self._fatal_error_code = None
@@ -5445,6 +5456,7 @@ def build_source(
         parent_chat_id: Optional[str] = None,
         message_id: Optional[str] = None,
         role_authorized: bool = False,
+        thread_initial_name: Optional[str] = None,
     ) -> SessionSource:
         """Helper to build a SessionSource for this platform."""
         # Normalize empty topic to None
@@ -5466,6 +5478,7 @@ def build_source(
             parent_chat_id=str(parent_chat_id) if parent_chat_id else None,
             message_id=str(message_id) if message_id else None,
             role_authorized=role_authorized,
+            thread_initial_name=str(thread_initial_name) if thread_initial_name else None,
         )
 
     @abstractmethod