deploy-woodpecker-agent runs on an agent; a synchronous 'systemctl restart
docker' kills the job's own container before the play finishes (pipeline
994 died at docker-install, before the daemon.json task even ran). Schedule
the restart via a transient systemd timer (systemd-run --on-active=15s) so
the playbook completes first, then docker restarts and picks up the IPv6
daemon.json.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>