Extract two pure helpers so they're testable without zustand/expo:
- settings-merge.ts: clampPageSize + forward-compatible mergeStoredSettings (the
upgrade path where stored data predates a new notification category must yield
the default, not undefined). stores/settings.ts now delegates.
- notify-format.ts: sanitizeBody (strip C0/DEL control chars, trim, cap at 200)
used for server-supplied notification text. stores/events.ts now imports it.
Behavior unchanged; typecheck clean.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
