Support volume preferences when picking the "best" asset file variation

Here’s the current implementation:

This feature would replace the current schemeIdx variant sort criterion with a new volumeIdx variant sort criterion.

The volume index would be configurable through a new “variantSortCriteriaVolumes” setting that takes an array of strings.

  • Each string would specify either a URI prefix (pslib:, psfile://volsha), or a volume label, or a volume mountpoint.

  • First volume to match “wins”.

  • Variations on unspecified volumes would be considered “worse” than the last specified volume.

  • variantSortCriteriaVolumes would default to


which is the current default for schemeIdx: it prefers files found in your library, then files on volumes with UUIDs, and then locally-mounted files on volumes without UUIDs, and then remote file shares without UUIDs.

variantSortCriteria would then default to