[ckpt] bug: btrfs loop device umount after reboot

[Ziqi002]

Component

ckpt

Bug Description

btrfs loop device umount after reboot
And when manual mount it, deamon can't reload snapshots

Steps to Reproduce

1. checkpoint in an machine without btrfis disk
2. reboot
3. ws-ckpt list

Expected Behavior

1. After reboot, loop device can't lose, and if it must lost, it should be able to be automatically mounted (the detection and mounting logic used during deamon startup can be reused. At this time, the img file should be detected and the subsequent process should be executed directly, and the snapshot information should be reloaded)
2. After manual mounting, it is necessary to be able to detect snapshots, or after mounting, systemctl restart can re detect snapshots

Environment

alinux4

Relevant Log Output

Additional Context

No response

[github-actions]

🔀 Issue Triage

This issue has been automatically assigned to @Ziqi002 as the maintainer(s) of ckpt.

Maintainers, please review and triage this issue. Set a priority label and update the status as needed. Thanks! 🙏