Rename app variable to demo in app.py for clarity and consistency in Gradio usage

app.py

@@ -34,7 +34,7 @@ def handle_message(persona, user_input, history):
         return history + [{"role": "assistant", "content": f"Error: {str(e)}"}]
 
 
-with gr.Blocks() as app:
+with gr.Blocks() as demo:
     gr.Markdown("## 🤖 LLMates: Persona-based Chat Assistant")
 
     persona = gr.Dropdown(
@@ -87,4 +87,4 @@ with gr.Blocks() as app:
 
 # main function
 if __name__ == "__main__":
-    app.launch()
+    demo.launch()