- Remove static Lisp_Object locals; use DEFSYM in syms_of_nsterm (GC-safe)
- Replace Lisp calls in accessibilityIndexForCharpos / charposForAccessibilityIndex
with NSString composed-character traversal (thread-safe, no Lisp needed)
- isAccessibilityFocused reads cachedPoint instead of marker_position off-thread
- Remove double-announcement: character nav uses only SelectedTextChanged
- Line announcement priority: High → Medium (avoid suppressing VO feedback)