Add ability to convert "ix-volume" to "host path"

[Stux]

@Duff1 documented an approach to do this manually

Moving from IX Volumes to Host Path Storage (not difficult!)

Save a copy of /mnt/.ix-apps/user_config.yaml Create the host paths you wish to use. Consult your existing app config (the list of iX Volumes) for what an app needs. The only notable requirement is user apps and group apps must own the folder. Stop the app you’re going to modify (if not modifying an app, it can continue to run while you make changes) Move existing app data into new host paths, e.g. rsync -a /mnt/.ix-apps/app_mounts/paperless-ngx/consume /mnt/pool0/data/apps/paperless-ngx/ If yo…