v1.12.0

Additive (MINOR) release: album-grouping and genre metadata. Backward-compatible — a 1.0.0
(or 1.11.0) pack is also a valid 1.12.0 pack, and an older reader ignores the new optional keys.

Added

• Album grouping + genre metadata (spec §5.1):
  four OPTIONAL, author-set top-level keys —

  • album_artist (string) — album artist for the release, so multi-artist / compilation
    albums group under one album identity; absent ⇒ falls back to artist.
  • track (int, 1-based) — track number within the album, for album playback order.
  • disc (int, 1-based, default 1) — disc number for multi-disc releases.
  • genres (list of strings, most specific first; genres[0] is primary) — genre labels.

  A reader predating 1.12.0 ignores all four.