e247dbc1be
- host_escrow_superseded table + SaveHostEscrow retains a different-sha old blob before overwrite (tx); same-sha idempotent (no supersede row); returns superseded bool. ACK/restore read the current row unchanged. CountSuperseded/ListSuperseded; DeleteHost drops retained rows. - escrow_superseded audit event + operator retained-count on host detail; register offbox_repo_orphaned/reset. Red-proof TestSaveHostEscrow_RetainsSuperseded.