Switch from a dynamically-derived registry/GITHUB_TOKEN login to the
same pattern already proven in the ebooks project: a fixed
git.arnef.de/arnef/nidus registry/image, docker/login-action with
REGISTRY_USERNAME/REGISTRY_PASSWORD repo secrets, docker/metadata-action
for tag/label generation (version, major.minor, latest, short SHA), and
a final buildx/system prune cleanup step. Also add a manual
workflow_dispatch trigger.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Builds linux/amd64 + linux/arm64 images via Buildx/QEMU whenever a "v*"
tag is pushed or a release is published, and pushes them (tagged with
the version and "latest") to this repository's own container registry.
Written in plain GitHub Actions syntax, which Gitea Actions runs as-is.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>