Fix: Add missing asyncio import in fastapi_app.py

src/server/fastapi_app.py

@@ -5,6 +5,7 @@ This module provides the main FastAPI application with proper CORS
 configuration, middleware setup, static file serving, and Jinja2 template
 integration.
 """
+import asyncio
 from contextlib import asynccontextmanager
 from pathlib import Path