[andresbott]

Summary

Albums could not be organised into user-defined collections such as box sets or series. This reads the GROUPING tag during scans and exposes the result as groupings in the API and web UI.

What

• Scanner and tag readers (taglib, ffprobe) extract GROUPING. A new grouping model and store link albums to groupings, and the metadata editor can write the tag.
• Subsonic gains an albumGroupings extension with endpoints for listing groupings and fetching a grouping's albums. The handler changes are in groupings.go, browsing.go and media.go.
• Library settings and the OpenAPI spec gain a groupings option, and the libraries handlers and catalog are updated to match.
• The web UI adds grouping cards, grid, list and detail views, a route, a sidebar entry, a library view tab, a grouping field in the metadata editor, and a grouping link on the album page.
• Docs are updated.

Notes

• Existing libraries need a rescan to populate groupings.