Support os.persistentStatePaths in Harvester configuration

[futuretea]

Problem:

Currently, Harvester OS does not support custom paths for persistent storage or read-write paths. This means that any changes made to files not in default persistentStatePaths will be lost upon reboot.

Solution:

To address this issue, this pull request adds a new options to the Harvester OS configuration in Harvester config.

The os.persistentStatePaths option allows users to configure custom paths where modifications made to files will persist across reboots. This means that any changes made to files in these paths will not be lost upon reboot.

an config example for install rook-ceph in Harvester

os:
  persistentStatePaths:
    - /var/lib/rook
  modules:
    - rbd
    - nbd

Without this PR, users can achieve the same effect by modifying /oem/90_custom.yaml and then rebootting. This PR allows users to define the desired os layout at installation time.

Related Issue:
harvester/harvester#3688

Note
Please ensure that any custom paths added using these options are valid and secure, and that any modifications made to the OS are done with caution and understanding of the potential risks.

Test plan:

Refer to harvester/harvester#3566

[futuretea]

@bk201 I've added a commit, added an os.rwPaths option to allow changes to the RW_PATHS configuration, and the PR documentation has been updated. CC @guangbochen

[futuretea]

@bk201 @guangbochen convert this PR to draft, try to add after-install-chroot in

harvester-installer/pkg/config/cos.go

Line 183 in 12eeb11

},

[bk201]

LGTM

[Vicente-Cheng]

LGTM!

[guangbochen]

LGTM, thanks.