Adds a `publish` job to ci.yml that fires only on green pushes to main. It
builds broker, server, and frontend from images/*.Dockerfile, tags each with
:main-<sha> + :latest, and pushes to the fleet registry at
redclaw-web-01:5000 (via its Tailscale IP 100.94.185.103, which the daemons
already trust in insecure-registries).
Adds a small systemd oneshot + 1-minute timer for gw-04 that polls :latest
of each service, pulls on drift, retags to the un-prefixed name the current
compose file uses, and rolls only the changed services. The retag keeps
/root/clawmates/docker-compose.yml unchanged for now — a follow-up can
migrate the compose file to registry-prefixed names once we're confident.
End-to-end: push to main -> tests -> images pushed -> gw-04 timer pulls
within ~1 min -> prod updated. Rollback = docker tag <old-sha> :latest and
`docker compose up -d`.
