R20E-R02 rollback guidance

#!/usr/bin/env bash
# R20E R02 installs no source. On STOP the retry service is restored and DEGRADED_POOL due time is normalized.
# Original pre-test snapshot from R01 is reused; rollback only after explicit operator decision:
ssh pve-mgts "qm rollback 101 r20e-pre-0720-132016"