Update Dockerfile

Dockerfile

@@ -89,7 +89,7 @@ BACKEND_PID=$!\n\
 \n\
 # Wait for backend to be ready\n\
 echo "⏳ Waiting for backend to start..."\n\
-sleep 5\n\
+sleep 30\n\
 \n\
 # Start frontend on port 7860 (HF Spaces exposed port)\n\
 echo "🎨 Starting Next.js frontend on port 7860..."\n\