ns: fix VoiceOver cursor sync — 8 changes from pipeline review

Changes applied (from vo-cursor pipeline review, 7 workers):

1. (Change 8) Add ns_ax_index_for_charpos helper, refactor
   ns_ax_index_for_point as thin wrapper — shared coordinate
   mapping for all accessibility attribute methods.

2. (Change 1) Remove Site A notifications from ns_draw_window_cursor.
   Eliminates duplicate VoiceOver notifications (Site A + Site B both
   fired for same events). Zoom cursor tracking (UAZoomChangeFocus)
   preserved.

3. (Change 7) Remove redundant bare ValueChanged before rich
   userInfo version in postAccessibilityUpdatesForWindow:.

4. (Change 2) Fix typing echo character extraction to use glyph-based
   index (ns_ax_index_for_point) instead of buffer-relative
   (pt - BUF_BEGV - 1).

5. (Change 3) Add AXTextStateChangeType:@2 (SelectionMove) userInfo
   to SelectedTextChanged notification for cursor movement —
   enables VoiceOver line-by-line reading on arrow keys.

6. (Change 4) Fix accessibilityRangeForPosition: to return
   glyph-based index via ns_ax_index_for_charpos instead of
   buffer-relative (charpos - BUF_BEGV).

7. (Change 5) Fix accessibilitySelectedTextRange mark branch to use
   ns_ax_index_for_charpos for both endpoints instead of mixing
   glyph-based point with buffer-relative mark.

8. Remove 10 redundant text methods from EmacsView (Group role
   should not expose text attributes — eliminates coordinate
   system divergence with EmacsAccessibilityBuffer).

9. Fix MRC leak: release EmacsAccessibilityBuffer after addObject:
   in ns_ax_collect_windows.

10. Remove dead lastAccessibilityModiff ivar (was only used by
    removed Site A).

Enum values verified from WebKit AXTextStateChangeIntent.h:
  AXTextStateChangeTypeEdit = 1
  AXTextStateChangeTypeSelectionMove = 2
  AXTextEditTypeTyping = 3

patches/0001-ns-implement-AXBoundsForRange-for-macOS-Zoom-cursor-.patch

@@ -52,7 +52,6 @@ MRC compatible.
 +  Lisp_Object lastSelectedWindow;
 +  @public
 +  NSRect lastAccessibilityCursorRect;
-+  ptrdiff_t lastAccessibilityModiff;
 +  @protected
  #endif
    BOOL font_panel_active;
@@ -89,61 +88,16 @@ MRC compatible.
    r = NSIntersectionRect (r, ns_row_rect (w, glyph_row, TEXT_AREA));
  
 +#ifdef NS_IMPL_COCOA
-+  /* Accessibility cursor tracking for macOS Zoom and VoiceOver.
++  /* Accessibility: store cursor rect for Zoom and bounds queries.
-+     Only notify AT when drawing the cursor in the active (selected)
++     VoiceOver notifications are handled solely by
-+     window.  Without this guard, C-x o triggers UAZoomChangeFocus
++     postAccessibilityUpdatesForWindow: (called from ns_update_end)
-+     for the old window last, snapping Zoom back.  */
++     to avoid duplicate notifications and mid-redisplay fragility.  */
 +  {
 +    EmacsView *view = FRAME_NS_VIEW (f);
 +    if (view && on_p && active_p)
 +      {
-+	/* Store cursor rect for accessibilityBoundsForRange: queries.  */
 +	view->lastAccessibilityCursorRect = r;
 +
-+	/* Find the focused virtual element — VoiceOver tracks IT,
-+	   not the EmacsView (AXGroup).  Notifications must come from
-+	   the element VoiceOver is monitoring.  */
-+	id axTarget = [view accessibilityFocusedUIElement];
-+	if (!axTarget)
-+	  axTarget = view;
-+
-+	struct buffer *curbuf
-+	  = XBUFFER (XWINDOW (f->selected_window)->contents);
-+
-+	if (curbuf && BUF_MODIFF (curbuf) != view->lastAccessibilityModiff)
-+	  {
-+	    /* Buffer content changed — typing echo.  Post ValueChanged
-+	       with rich userInfo on the FOCUSED ELEMENT.
-+	       kAXTextStateChangeTypeEdit = 1, kAXTextEditTypeTyping = 3.  */
-+	    view->lastAccessibilityModiff = BUF_MODIFF (curbuf);
-+
-+	    NSString *changedText = @"";
-+	    ptrdiff_t pt = BUF_PT (curbuf);
-+	    if (pt > BUF_BEGV (curbuf))
-+	      {
-+		NSRange charRange = NSMakeRange (
-+		  (NSUInteger)(pt - BUF_BEGV (curbuf) - 1), 1);
-+		changedText = [view accessibilityStringForRange:charRange];
-+		if (!changedText)
-+		  changedText = @"";
-+	      }
-+
-+	    NSDictionary *change = @{
-+	      @"AXTextEditType": @3,
-+	      @"AXTextChangeValue": changedText
-+	    };
-+	    NSDictionary *userInfo = @{
-+	      @"AXTextStateChangeType": @1,
-+	      @"AXTextChangeValues": @[change]
-+	    };
-+	    NSAccessibilityPostNotificationWithUserInfo (
-+	      axTarget, NSAccessibilityValueChangedNotification, userInfo);
-+	  }
-+
-+	/* Always notify cursor movement on the focused element.  */
-+	NSAccessibilityPostNotification (
-+	  axTarget, NSAccessibilitySelectedTextChangedNotification);
-+
 +	/* Tell macOS Zoom where the cursor is.  UAZoomChangeFocus()
 +	   expects top-left origin (CG coordinate space).  */
 +	if (UAZoomEnabled ())
@@ -401,19 +355,16 @@ MRC compatible.
 +}
 +
 +
-+/* Compute the character index within glyph-extracted text that
++/* Compute the glyph-based character index for an arbitrary buffer
-+   corresponds to the buffer point position.  */
++   charpos within the visible glyph rows of window W.  All accessibility
++   attribute methods must use this (or its wrapper ns_ax_index_for_point)
++   to stay in the same coordinate space as accessibilityValue.  */
 +static NSUInteger
-+ns_ax_index_for_point (struct window *w)
++ns_ax_index_for_charpos (struct window *w, ptrdiff_t charpos)
 +{
 +  if (!w || !w->current_matrix || !WINDOW_LEAF_P(w))
 +    return 0;
 +
-+  struct buffer *b = XBUFFER(w->contents);
-+  if (!b)
-+    return 0;
-+
-+  ptrdiff_t point = BUF_PT(b);
 +  struct glyph_matrix *matrix = w->current_matrix;
 +  NSUInteger pos = 0;
 +
@@ -428,10 +379,10 @@ MRC compatible.
 +      ptrdiff_t row_start = MATRIX_ROW_START_CHARPOS (row);
 +      ptrdiff_t row_end = MATRIX_ROW_END_CHARPOS (row);
 +
-+      if (point >= row_start && point < row_end)
++      if (charpos >= row_start && charpos < row_end)
 +        {
-+          /* Point is within this row.  Count visible glyphs whose
++          /* Charpos is within this row.  Count visible glyphs whose
-+             buffer charpos is before point.  */
++             buffer charpos is before the target.  */
 +          int chars_before = 0;
 +          struct glyph *g = row->glyphs[TEXT_AREA];
 +          struct glyph *gend = g + row->used[TEXT_AREA];
@@ -439,7 +390,7 @@ MRC compatible.
 +            {
 +              if (g->type == CHAR_GLYPH && !g->padding_p
 +                  && g->charpos >= row_start
-+                  && g->charpos < point)
++                  && g->charpos < charpos)
 +                {
 +                  unsigned ch = g->u.ch;
 +                  if (ch != '\n' && ch != '\r' && ch >= 32)
@@ -467,6 +418,18 @@ MRC compatible.
 +  return pos > 0 ? pos - 1 : 0;
 +}
 +
++/* Convenience wrapper: glyph-based index for buffer point.  */
++static NSUInteger
++ns_ax_index_for_point (struct window *w)
++{
++  if (!w || !WINDOW_LEAF_P(w))
++    return 0;
++  struct buffer *b = XBUFFER(w->contents);
++  if (!b)
++    return 0;
++  return ns_ax_index_for_charpos (w, BUF_PT(b));
++}
++
 +
 +@implementation EmacsAccessibilityElement
 +
@@ -596,17 +559,14 @@ MRC compatible.
 +  if (NILP(BVAR(b, mark_active)))
 +    return NSMakeRange(point_idx, 0);
 +
-+  /* With active mark, report the selection range.  Map mark
++  /* With active mark, report the selection range.  Both endpoints
-+     position to accessibility index using the same glyph-based
++     must be mapped to glyph-based indices consistent with
-+     mapping as point.  */
++     accessibilityValue (via ns_ax_index_for_charpos).  */
 +  ptrdiff_t mark_pos = marker_position (BVAR (b, mark));
-+  ptrdiff_t pt_pos = BUF_PT (b);
++  NSUInteger mark_idx = ns_ax_index_for_charpos (w, mark_pos);
-+  ptrdiff_t begv = BUF_BEGV (b);
++  NSUInteger start_idx = MIN (point_idx, mark_idx);
-+  ptrdiff_t sel_start = (mark_pos < pt_pos) ? mark_pos : pt_pos;
++  NSUInteger end_idx = MAX (point_idx, mark_idx);
-+  ptrdiff_t sel_end = (mark_pos < pt_pos) ? pt_pos : mark_pos;
++  return NSMakeRange (start_idx, end_idx - start_idx);
-+  NSUInteger start_idx = (NSUInteger) (sel_start - begv);
-+  NSUInteger len = (NSUInteger) (sel_end - sel_start);
-+  return NSMakeRange(start_idx, len);
 +}
 +
 +- (NSInteger)accessibilityInsertionPointLineNumber
@@ -719,15 +679,10 @@ MRC compatible.
 +      glyph_x += glyph->pixel_width;
 +    }
 +
-+  /* Convert buffer charpos to accessibility index.  */
++  /* Convert buffer charpos to glyph-based accessibility index,
-+  struct buffer *b = XBUFFER (w->contents);
++     consistent with accessibilityValue coordinate space.  */
-+  if (!b)
++  NSUInteger ax_idx = ns_ax_index_for_charpos (w, best_charpos);
-+    return NSMakeRange (0, 0);
++  return NSMakeRange (ax_idx, 1);
-+
-+  ptrdiff_t idx = best_charpos - BUF_BEGV (b);
-+  if (idx < 0) idx = 0;
-+
-+  return NSMakeRange ((NSUInteger) idx, 1);
 +}
 +
 +- (NSRange)accessibilityVisibleCharacterRange
@@ -762,22 +717,19 @@ MRC compatible.
 +  ptrdiff_t modiff = BUF_MODIFF(b);
 +  ptrdiff_t point = BUF_PT(b);
 +
-+  /* Text content changed?  */
++  /* Text content changed?  Post ValueChanged with typing echo userInfo.
++     Single notification (no bare ValueChanged first) — Chromium pattern.
++     kAXTextStateChangeTypeEdit = 1, kAXTextEditTypeTyping = 3
++     (verified from WebKit AXTextStateChangeIntent.h).  */
 +  if (modiff != self.cachedModiff)
 +    {
 +      self.cachedModiff = modiff;
-+      NSAccessibilityPostNotification(self,
-+        NSAccessibilityValueChangedNotification);
 +
-+      /* Rich typing echo for VoiceOver.
-+         kAXTextStateChangeTypeEdit = 1, kAXTextEditTypeTyping = 3.
-+         Must include AXTextChangeValues array for VoiceOver to speak.  */
 +      NSString *changedText = @"";
-+      ptrdiff_t pt = BUF_PT (b);
++      NSUInteger point_idx = ns_ax_index_for_point (w);
-+      if (pt > BUF_BEGV (b))
++      if (point_idx > 0)
 +        {
-+          NSRange charRange = NSMakeRange (
++          NSRange charRange = NSMakeRange (point_idx - 1, 1);
-+            (NSUInteger)(pt - BUF_BEGV (b) - 1), 1);
 +          changedText = [self accessibilityStringForRange:charRange];
 +          if (!changedText)
 +            changedText = @"";
@@ -795,12 +747,20 @@ MRC compatible.
 +        self, NSAccessibilityValueChangedNotification, userInfo);
 +    }
 +
-+  /* Cursor moved?  */
++  /* Cursor moved?  Post with userInfo so VoiceOver distinguishes
++     navigation from programmatic selection changes and triggers
++     line-by-line reading.
++     kAXTextStateChangeTypeSelectionMove = 2.  */
 +  if (point != self.cachedPoint)
 +    {
 +      self.cachedPoint = point;
-+      NSAccessibilityPostNotification(self,
++      NSDictionary *moveInfo = @{
-+        NSAccessibilitySelectedTextChangedNotification);
++        @"AXTextStateChangeType": @2
++      };
++      NSAccessibilityPostNotificationWithUserInfo(
++        self,
++        NSAccessibilitySelectedTextChangedNotification,
++        moveInfo);
 +    }
 +}
 +
@@ -876,6 +836,7 @@ MRC compatible.
 +        }
 +
 +      [elements addObject:elem];
++      [elem release];  /* array retains; balance the alloc */
 +    }
 +  else
 +    {
@@ -1016,185 +977,6 @@ MRC compatible.
 +  return [self accessibilityBoundsForRange:range];
 +}
 +
-+/* ---- Text content methods (for Zoom and legacy AT) ---- */
-+
-+- (id)accessibilityValue
-+{
-+  if (!emacsframe)
-+    return @"";
-+
-+  struct buffer *curbuf
-+    = XBUFFER (XWINDOW (emacsframe->selected_window)->contents);
-+  if (!curbuf)
-+    return @"";
-+
-+  ptrdiff_t start_byte = BUF_BEGV_BYTE (curbuf);
-+  ptrdiff_t byte_range = BUF_ZV_BYTE (curbuf) - start_byte;
-+  ptrdiff_t range = BUF_ZV (curbuf) - BUF_BEGV (curbuf);
-+
-+  if (range > 10000)
-+    {
-+      range = 10000;
-+      ptrdiff_t end_byte = buf_charpos_to_bytepos (curbuf,
-+						    BUF_BEGV (curbuf) + range);
-+      byte_range = end_byte - start_byte;
-+    }
-+
-+  Lisp_Object str;
-+  if (! NILP (BVAR (curbuf, enable_multibyte_characters)))
-+    str = make_uninit_multibyte_string (range, byte_range);
-+  else
-+    str = make_uninit_string (range);
-+  memcpy (SDATA (str), BYTE_POS_ADDR (start_byte), byte_range);
-+
-+  return [NSString stringWithLispString:str];
-+}
-+
-+- (NSRange)accessibilitySelectedTextRange
-+{
-+  if (!emacsframe)
-+    return NSMakeRange (0, 0);
-+
-+  struct buffer *curbuf
-+    = XBUFFER (XWINDOW (emacsframe->selected_window)->contents);
-+  if (!curbuf)
-+    return NSMakeRange (0, 0);
-+
-+  ptrdiff_t pt = BUF_PT (curbuf) - BUF_BEGV (curbuf);
-+  return NSMakeRange ((NSUInteger) pt, 0);
-+}
-+
-+- (NSString *)accessibilityStringForRange:(NSRange)nsrange
-+{
-+  if (!emacsframe)
-+    return @"";
-+
-+  struct buffer *curbuf
-+    = XBUFFER (XWINDOW (emacsframe->selected_window)->contents);
-+  if (!curbuf)
-+    return @"";
-+
-+  ptrdiff_t start = BUF_BEGV (curbuf) + (ptrdiff_t) nsrange.location;
-+  ptrdiff_t end = start + (ptrdiff_t) nsrange.length;
-+  ptrdiff_t buf_end = BUF_ZV (curbuf);
-+
-+  if (start < BUF_BEGV (curbuf)) start = BUF_BEGV (curbuf);
-+  if (end > buf_end) end = buf_end;
-+  if (start >= end) return @"";
-+
-+  ptrdiff_t start_byte = buf_charpos_to_bytepos (curbuf, start);
-+  ptrdiff_t end_byte = buf_charpos_to_bytepos (curbuf, end);
-+  ptrdiff_t char_range = end - start;
-+  ptrdiff_t brange = end_byte - start_byte;
-+
-+  Lisp_Object str;
-+  if (! NILP (BVAR (curbuf, enable_multibyte_characters)))
-+    str = make_uninit_multibyte_string (char_range, brange);
-+  else
-+    str = make_uninit_string (char_range);
-+  memcpy (SDATA (str), BUF_BYTE_ADDRESS (curbuf, start_byte), brange);
-+
-+  return [NSString stringWithLispString:str];
-+}
-+
-+- (NSInteger)accessibilityNumberOfCharacters
-+{
-+  if (!emacsframe)
-+    return 0;
-+  struct buffer *curbuf
-+    = XBUFFER (XWINDOW (emacsframe->selected_window)->contents);
-+  if (!curbuf)
-+    return 0;
-+  ptrdiff_t range = BUF_ZV (curbuf) - BUF_BEGV (curbuf);
-+  return (NSInteger) MIN (range, 10000);
-+}
-+
-+- (NSString *)accessibilitySelectedText
-+{
-+  if (!emacsframe)
-+    return @"";
-+  struct buffer *curbuf
-+    = XBUFFER (XWINDOW (emacsframe->selected_window)->contents);
-+  if (!curbuf || NILP (BVAR (curbuf, mark_active)))
-+    return @"";
-+  return @"";
-+}
-+
-+- (NSInteger)accessibilityInsertionPointLineNumber
-+{
-+  if (!emacsframe)
-+    return 0;
-+  struct window *w = XWINDOW (emacsframe->selected_window);
-+  if (!w)
-+    return 0;
-+  return (NSInteger) (w->cursor.vpos);
-+}
-+
-+- (NSRange)accessibilityVisibleCharacterRange
-+{
-+  if (!emacsframe)
-+    return NSMakeRange (0, 0);
-+  struct buffer *curbuf
-+    = XBUFFER (XWINDOW (emacsframe->selected_window)->contents);
-+  if (!curbuf)
-+    return NSMakeRange (0, 0);
-+  ptrdiff_t range = BUF_ZV (curbuf) - BUF_BEGV (curbuf);
-+  return NSMakeRange (0, (NSUInteger) MIN (range, 10000));
-+}
-+
-+- (NSAttributedString *)accessibilityAttributedStringForRange:(NSRange)range
-+{
-+  NSString *str = [self accessibilityStringForRange:range];
-+  return [[[NSAttributedString alloc] initWithString:str] autorelease];
-+}
-+
-+- (NSInteger)accessibilityLineForIndex:(NSInteger)index
-+{
-+  if (!emacsframe)
-+    return 0;
-+  struct window *w = XWINDOW (emacsframe->selected_window);
-+  if (!w || !w->current_matrix)
-+    return 0;
-+  struct buffer *curbuf = XBUFFER (w->contents);
-+  if (!curbuf)
-+    return 0;
-+  ptrdiff_t charpos = BUF_BEGV (curbuf) + (ptrdiff_t) index;
-+  struct glyph_matrix *matrix = w->current_matrix;
-+  for (int i = 0; i < matrix->nrows; i++)
-+    {
-+      struct glyph_row *row = matrix->rows + i;
-+      if (!row->enabled_p)
-+	continue;
-+      if (MATRIX_ROW_START_CHARPOS (row) <= charpos
-+	  && charpos < MATRIX_ROW_END_CHARPOS (row))
-+	return (NSInteger) i;
-+    }
-+  return 0;
-+}
-+
-+- (NSRange)accessibilityRangeForLine:(NSInteger)line
-+{
-+  if (!emacsframe)
-+    return NSMakeRange (0, 0);
-+  struct window *w = XWINDOW (emacsframe->selected_window);
-+  if (!w || !w->current_matrix)
-+    return NSMakeRange (0, 0);
-+  struct buffer *curbuf = XBUFFER (w->contents);
-+  if (!curbuf)
-+    return NSMakeRange (0, 0);
-+  struct glyph_matrix *matrix = w->current_matrix;
-+  if (line < 0 || line >= matrix->nrows)
-+    return NSMakeRange (0, 0);
-+  struct glyph_row *row = matrix->rows + line;
-+  if (!row->enabled_p)
-+    return NSMakeRange (0, 0);
-+  ptrdiff_t start = MATRIX_ROW_START_CHARPOS (row) - BUF_BEGV (curbuf);
-+  ptrdiff_t end = MATRIX_ROW_END_CHARPOS (row) - BUF_BEGV (curbuf);
-+  if (start < 0) start = 0;
-+  if (end < start) end = start;
-+  return NSMakeRange ((NSUInteger) start, (NSUInteger) (end - start));
-+}
-+
 +/* ---- Legacy parameterized attribute APIs (Zoom uses these) ---- */
 +
 +- (NSArray *)accessibilityParameterizedAttributeNames