- New hero layout: cover (play/pause) + waveform + title/time over a stripped
  queue; multi-track + per-track chapters (active row expands, waveform markers).
- New grid layout: cover-art cards + a slim now-playing bar (above/below).
- Single chaptered track → seekable chapter list + waveform markers.
- Options (data-*/JS): coverSize, thumbnailSize (+ --wp-thumb-size), density,
  coverPosition, barPosition, showSubtitle.
- Active row/card click now toggles play/pause (was restart); togglePlay reads
  the audio element's paused state. Adds CHANGELOG.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>