fix: proxy backend to localhost in nginx config

frontend/nginx.conf

@@ -14,7 +14,7 @@ server {
     # Any request to http://<your-space-url>/api/...
     # will be forwarded to http://backend:8000/...
     location /api {
-        proxy_pass http://backend:8000; # 'backend' is the service name in docker-compose.yml
+        proxy_pass http://127.0.0.1:8000; # 'backend' is the service name in docker-compose.yml
         proxy_set_header Host $host;
         proxy_set_header X-Real-IP $remote_addr;
         proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;