build-and-push failed at docker/setup-buildx-action: the job had no
/var/run/docker.sock, so buildx's docker-container driver couldn't reach
the daemon. Mount the host socket into build-and-push and deploy, and
replace setup-buildx + build-push-action (+ the unsupported gha cache)
with a plain docker build/push against the host daemon (DooD), reusing
the host's layer cache.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
