Runner now runs in a quadlet container on caddy-net, so 127.0.0.1
is the runner's own loopback. Reach the Caddy container by name
('caddy') with --connect-to keeping SNI/Host as the public hostname
so the right vhost matches.
Also adds the tag trigger: push of zddc-server-v[0-9]+.[0-9]+.[0-9]+
auto-cuts a stable release. The lockstep set pushes six tags at once;
filtering on zddc-server-v* gives exactly one workflow run per cut.
Re-cutting at the tagged commit is safe — _promote_stable in
shared/build-lib.sh is idempotent re: tag creation.
Forgejo Actions workflow that runs ./build alpha|beta|release [version]
followed by ./deploy --releases. Uses the host-mode runner so the
behavior is identical to manual cuts. Tag-trigger added later once
the dispatch path is exercised.
