Enhance file system plugin infra to support mount options

[votdev]

Enhance the file system UI infra to support individual mount options. This is useful to support BTRFS compression for example.

[UltimateByte]

Meanwhile, to enable compression in BTRFS, you can apply the following workaround:

1. Edit /etc/openmediavault/config.xml, find your volume's UUID. In <opts> section, replace: <opts>defaults,nofail</opts> With: <opts>defaults,nofail,compress=zstd</opts>
2. Apply with: omv-salt deploy run fstab

Note: Seems like "defaults" already includes zstd compression, at least with Debian 13 and OMV8 beta:

root@nas:~# findmnt -no OPTIONS /srv/dev-disk-by-uuid-xxx-xxx-xxx-xxx
rw,relatime,compress=zstd:3,space_cache=v2,subvolid=5,subvol=/