Adds a separate workflow that builds the server image and pushes it to GHCR under
non-production tags (beta, branch slug, sha-<commit>, and an optional custom tag
via manual dispatch) so the host-control branch can be deployed to a staging /
backup server and used as a custom server — without ever touching ':latest' that
the official relay tracks (flavor: latest=false).
Runs on push to feature/host-control-mode and on workflow_dispatch. Remove once
the feature is merged and released normally.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Timo