The servers bind IPv4 (0.0.0.0) only. busybox wget resolves `localhost`
to ::1 first and does not fall back to IPv4, so the healthcheck failed
with "connection refused" and the container showed as unhealthy while
serving fine. Verified on the production api container.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>