Revert "gpt-4.1-nano: Drop fill width."

This reverts commit 290f4f06aa5b682ea13a481ca28079df5fce2be9.

app.py

@@ -36,7 +36,8 @@ gr.load_chat(
         ["Explain about quantum computers."]
     ],  # Provide sample inputs for users to try
     cache_examples=False,  # Ensure responses always fresh
-    show_api=False  # Disable Gradio API
+    show_api=False,  # Disable Gradio API
+    fill_width=True  # Auto width, adjust to the monitor screen
 ).launch(
     max_file_size="1mb",  # Max image upload size limit
     server_name="0.0.0.0"  # Listen on all network interfaces