Served by the nginx-stub pod on the flight-server VPS node.
This is the catch-all for any Host that does not match a real site, including
requests made directly to the node's IP.
It has no PHP, no database, no cache and performs no DNS lookups, so it keeps
answering during a home control-plane outage. If /healthz
returns ok while a real site fails, the ingress path is healthy and the
fault is in that site's PHP-FPM / database layer.
Health check: curl -s http://<vps-ip>/healthz