updates/health.sh: 43 checks across all services (API answers, git refs, a push
message round trip, SSO redirects and token endpoint, mesh state, backup age).
updates/update.sh: per service pull or build, snapshot, recreate, wait for the
health check, put image and data back on red and stop the run.
backup/backup.sh: online dumps for n8n, Pocket ID and tinyauth; BACKUP_TAG so
pre-update snapshots are not removed by the nightly keep-daily rule.
compose.yml and caddy/Dockerfile: exact versions instead of latest, 16, 7-alpine
and caddy:2-alpine.
