dsh 回滚

undohaven list && undohaven restore --to <snapshot-id>。列出本机快照再回滚。恢复前会先做一份安全快照，dsh 还占着锁时会拒绝。

undohaven list && undohaven restore --to <snapshot-id>. List local snapshots and roll the dsh home back. A safety snapshot is taken first, and restore refuses to run while dsh is still holding a lock.