feat: add group/channel support for Telegram bot

- Add TELEGRAM_GROUP_IDS configuration setting to enable optional group/channel filtering
- Add _is_group_enabled() authorization check to all command handlers
- Add group/channel authorization check to message_handler
- All handlers now verify both user authorization and group authorization
- If TELEGRAM_GROUP_IDS is not configured, bot accepts messages from any group
- If TELEGRAM_GROUP_IDS is configured, bot only processes messages from those groups

This enables the bot to be used in group chats and channels with Topics/Threads support.

steward/bot/telegram.py

@@ -75,6 +75,13 @@ def _is_allowed(user_id: int, settings: Settings) -> bool:
     return user_id in settings.telegram_allowed_user_ids
 
 
+def _is_group_enabled(chat_id: int, settings: Settings) -> bool:
+    """Return True if the group/channel is in the configured list (or no list is configured)."""
+    if not settings.telegram_group_ids:
+        return True
+    return chat_id in settings.telegram_group_ids
+
+
 async def _send_long(update: Update, text: str) -> None:
     """Send text, splitting across messages if it exceeds Telegram's 4096-char limit."""
     limit = 4096
@@ -92,6 +99,10 @@ async def start_handler(update: Update, context: ContextTypes.DEFAULT_TYPE) -> N
     if user is None or not _is_allowed(user.id, settings):
         return
 
+    chat = update.effective_chat
+    if chat is None or not _is_group_enabled(chat.id, settings):
+        return
+
     await update.message.reply_text(  # type: ignore[union-attr]
         "Hello, I'm *Steward* \U0001f916\n\n"
         "I'm your AI-assisted personal operations platform.\n"
@@ -112,6 +123,10 @@ async def help_handler(update: Update, context: ContextTypes.DEFAULT_TYPE) -> No
     if user is None or not _is_allowed(user.id, settings):
         return
 
+    chat = update.effective_chat
+    if chat is None or not _is_group_enabled(chat.id, settings):
+        return
+
     await update.message.reply_text(  # type: ignore[union-attr]
         "*Steward commands*\n\n"
         "/start – greeting\n"
@@ -136,6 +151,10 @@ async def clear_handler(update: Update, context: ContextTypes.DEFAULT_TYPE) -> N
     if user is None or not _is_allowed(user.id, settings):
         return
 
+    chat = update.effective_chat
+    if chat is None or not _is_group_enabled(chat.id, settings):
+        return
+
     key = _thread_key(update)
     if key is not None:
         _thread_history[key].clear()
@@ -167,6 +186,10 @@ async def flush_handler(update: Update, context: ContextTypes.DEFAULT_TYPE) -> N
     if user is None or not _is_allowed(user.id, settings):
         return
 
+    chat = update.effective_chat
+    if chat is None or not _is_group_enabled(chat.id, settings):
+        return
+
     key = _thread_key(update)
     if key is None:
         await update.message.reply_text(  # type: ignore[union-attr]
@@ -246,6 +269,10 @@ async def recall_handler(update: Update, context: ContextTypes.DEFAULT_TYPE) ->
     if user is None or not _is_allowed(user.id, settings):
         return
 
+    chat = update.effective_chat
+    if chat is None or not _is_group_enabled(chat.id, settings):
+        return
+
     # If the user supplied a keyword query, search the knowledge base
     args: list[str] = context.args or []  # type: ignore[assignment]
     if args:
@@ -306,13 +333,16 @@ async def analyse_handler(update: Update, context: ContextTypes.DEFAULT_TYPE) ->
     if user is None or not _is_allowed(user.id, settings):
         return
 
+    chat = update.effective_chat
+    if chat is None or not _is_group_enabled(chat.id, settings):
+        return
+
     await update.message.reply_text("Running analysis, please wait...")  # type: ignore[union-attr]
     generator = ProposalGenerator(settings, llm)
     proposal = await generator.run()
     if proposal is None:
         await update.message.reply_text(  # type: ignore[union-attr]
-            "Analysis could not be completed. "
-            "Check that `ANALYSIS_TARGET_URL` is configured."
+            "Analysis could not be completed. Check that `ANALYSIS_TARGET_URL` is configured."
         )
         return
 
@@ -356,8 +386,11 @@ async def message_handler(update: Update, context: ContextTypes.DEFAULT_TYPE) ->
     store: ThreadMemoryStore = context.bot_data["thread_store"]
     tool_client: ToolClient | None = context.bot_data.get("tool_client")
     user = update.effective_user
+    chat = update.effective_chat
     if user is None or not _is_allowed(user.id, settings):
         return
+    if chat is None or not _is_group_enabled(chat.id, settings):
+        return
 
     text = update.message.text  # type: ignore[union-attr]
     if not text:
@@ -402,6 +435,8 @@ def build_application(
     app.bot_data["llm"] = llm
     app.bot_data["thread_store"] = thread_store or ThreadMemoryStore(settings.thread_memory_path)
     app.bot_data["tool_client"] = tool_client  # None when tools are not configured
+    logger.info("Configured allowed users: %s", settings.telegram_allowed_user_ids)
+    logger.info("Configured group IDs: %s", settings.telegram_group_ids)
 
     app.add_handler(CommandHandler("start", start_handler))
     app.add_handler(CommandHandler("help", help_handler))