fix bugs

app.py

@@ -209,7 +209,7 @@ def http_bot(state):
     final_response = output
     logging.info(f"Text-only Reasoning: {final_response}")
     state.messages[-1][-1] = state.messages[-1][-1][:-1]
-    yield (state, state.to_gradio_chatbot_public()) + (disable_btn,) * 2
+    yield (state, state.to_gradio_chatbot_public()) + (enable_btn,) * 2
 
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