0.13.0

Added

• Listening stats — a new Stats view (bar-chart icon in the top bar)
  showing total time listened, books finished, your current day streak,
  top 5 authors and narrators, and a 12-week listening pace chart. Streak
  and pace start tracking from this version forward — there's no historical
  data to back-fill from before now.

Fixed

• Ebook read-along pairings (ebook-pairings.json) were never actually
  loaded from disk at startup — every launch silently re-scanned the whole
  library for matches and could overwrite a manually-picked pairing with a
  fresh auto-guess. Pairings now load correctly on launch.