feat: Show user message immediately before bot response

UX improvement: User input now displays instantly

✨ Enhancement:
- Use generator (yield) to show user message immediately
- First yield: Display user message right after input
- Second yield: Add bot response when generation completes
- Improves perceived responsiveness

🎯 User Experience:
- Before: User message appears only after bot response (slow)
- After: User message appears instantly (fast)
- Better feedback during bot response generation

📝 Implementation:
- Changed submit() to generator function
- First yield: history + user message
- Second yield: history + user message + bot response

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

app.py

@@ -224,10 +224,14 @@ with gr.Blocks(title="🤖 Llama-2-Ko Chatbot") as demo:
     clear = gr.Button("🗑️ 대화 초기화", size="sm")
 
     def submit(message, history):
-        # Gradio automatically adds user message when type="messages"
-        # We just need to get the bot response
-        response_history = chat_wrapper(message, history)
-        return response_history, ""
+        # Immediately show user message
+        updated_history = history + [{"role": "user", "content": message}]
+        # Return updated history first (shows user message immediately)
+        # Then generate bot response
+        yield updated_history, ""
+        # Generate and add bot response
+        final_history = chat_wrapper(message, history)
+        yield final_history, ""
 
     btn.click(submit, [msg, chatbot], [chatbot, msg])
     msg.submit(submit, [msg, chatbot], [chatbot, msg])