Update http_bot to unpack user message from get_user_message for improved clarity

app.py

@@ -263,7 +263,7 @@ def http_bot(
 
     try:
         # Stream output
-        message = state.get_user_message(source=state.USER, position='last')
+        _, message = state.get_user_message(source=state.USER, position='last')
         logger.info(f"==== User message ====\n{message}")
         logger.info(f"==== Image paths ====\n{all_image_paths}")