build-golden.sh bakes a small OS rootfs + a dedicated /var/lib/docker volume
(mp0, backup=1) carrying the baked images, plus Docker log rotation. bringup.go
grows the golden's data volume to the per-customer target (DataVolGrowGB) and
emits backup=1 on data mounts (GuestMount.Backup) — closing the spike-B3 silent
DB-loss trap. CLI gains -rootfs-grow/-datavol-grow/-datavol-mount. New
RUNBOOK-provisioning-storage.md. Phase 2 = felhom-controller v0.58.0.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>