fix: wrap callback router in try/except to expose swallowed errors

worker/src/bot.py

@@ -434,13 +434,23 @@ async def text_input_handler(update: Update, context: ContextTypes.DEFAULT_TYPE)
 
 async def callback_router(update: Update, context: ContextTypes.DEFAULT_TYPE) -> None:
     """Route all callback queries by prefix pattern."""
+    try:
+        _handle_callback(update, context)
+    except Exception:
+        logger.exception("Callback handler error for %s", update.callback_query.data if update.callback_query else "unknown")
+
+
+async def _handle_callback(update: Update, context: ContextTypes.DEFAULT_TYPE) -> None:
     query = update.callback_query
     if not query or not query.data:
         return
 
     await query.answer()  # dismiss loading indicator
+    logger.info("Callback received: %s", query.data)
+
     user = await _require_user(update)
     if not user:
+        logger.warning("Callback rejected: user not found or inactive")
         return
 
     data = query.data