The Dockerfile's builder stage already runs the unit suite, so the workflow
deliberately has no separate test job -- a red test cannot produce an image.
After pushing, the published artifact is smoke-tested by digest: `--version`
covers a runtime stage missing a shared library, and `--check` against a
throwaway credentials file covers the config baked into the image. Both were
failure modes a green build would not have caught. The `--check` invocation is
verified locally against docker/openvpngate.conf.
`latest` follows the newest v* tag rather than the branch head; master head is
published as `master`. Registry paths are lowercased explicitly rather than
relying on metadata-action, since the same value is reused for the smoke test.
GHCR_TOKEN / GHCR_USER / GHCR_IMAGE override the built-ins so this still works
from a mirror or a Gitea/Forgejo runner, where the ambient token authenticates
to the wrong registry. On github.com none of them need to be set.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
