- New: User Phrase Manager. Add, edit, search, and delete your
  own phrases under Settings → User Phrase Manager. Your phrases
  are always ranked ahead of the bundled corpus for matching
  keystrokes, with an "Analyse Roots" button that derives the
  canonical EZ keystrokes from the phrase length and per-char
  encoding rules. Per-phrase use is tracked so frequently used
  user phrases overtake older ones on the same prefix. CSV
  backup / restore included.
- New: Backup & Restore. Settings → Backup & Restore now exports
  your user phrases and learned dictionary frequencies as a
  single .rkbak.gz file, and restores them by merging into the
  existing database — so reinstalling or switching phones no
  longer wipes the personal state the app has accumulated.
  Imports treat the picked file as untrusted: size cap, strict
  decode, per-row validation, EZ-keystroke check.
- Improved: keystroke suggestions in the Add-Phrase dialog now
  surface the corpus's own phrase-level encoding first (e.g.
  八一七公報 → 8178) instead of starting with the per-char
  fall-back.
- Internal: targetSdk bumped to 37; dependencies refreshed
  (Compose BOM, kotlinx-coroutines).
