fix: add missing os import in app.py

- Added os import to fix NameError when accessing environment variables
- Required for REQUESTS_TIMEOUT environment variable

app.py

@@ -8,6 +8,7 @@ Provides a chat interface to interact with the autonomous agent teams:
 - Team D: Crypto & Sports Trading
 """
 
+import os
 import gradio as gr
 from fastapi import FastAPI, HTTPException
 from fastapi.middleware.cors import CORSMiddleware