patches: auto-detect Zoom/VoiceOver; single variable gates both

Changes:
- EmacsApp gets ns_update_accessibility_state and
  ns_accessibility_did_change: methods (patch 0005)
- At startup: UAZoomEnabled() + AXIsProcessTrustedWithOptions()
  determine initial ns_accessibility_enabled state
- com.apple.accessibility.api distributed notification updates it
  whenever any AT connects or disconnects
- All Zoom call sites (UAZoomChangeFocus) now gated by
  ns_accessibility_enabled in addition to ns_zoom_enabled_p()
- ns-accessibility-enabled docstring updated to describe auto-detect

Result: zero config needed; zero overhead when no AT is active;
single variable overrides auto-detection when needed.

patches/0008-ns-announce-child-frame-completion-candidates-for-Vo.patch

@@ -1,4 +1,4 @@
-From 2466072f55f562d96d189814815bf8c4084338b5 Mon Sep 17 00:00:00 2001
+From 2dabc7e44d316fa29e64958383fbac230f0f6870 Mon Sep 17 00:00:00 2001
 From: Martin Sukany <martin@sukany.cz>
 Date: Sat, 28 Feb 2026 16:01:29 +0100
 Subject: [PATCH 9/9] ns: announce child frame completion candidates for
@@ -109,10 +109,10 @@ index 2102fb9..dd98d56 100644
  @end
  
 diff --git a/src/nsterm.m b/src/nsterm.m
-index 71b6d2e..fd7c520 100644
+index 5654283..69644d5 100644
 --- a/src/nsterm.m
 +++ b/src/nsterm.m
-@@ -7353,6 +7353,112 @@ visual line index for Zoom (skip whitespace-only lines
+@@ -7401,6 +7401,112 @@ visual line index for Zoom (skip whitespace-only lines
  
    return nil;
  }
@@ -225,7 +225,7 @@ index 71b6d2e..fd7c520 100644
  /* Build accessibility text for window W, skipping invisible text.
     Populates *OUT_START with the buffer start charpos.
     Populates *OUT_RUNS with an array of visible runs and *OUT_NRUNS
-@@ -8097,16 +8203,25 @@ - (void)ensureTextCache
+@@ -8145,16 +8251,25 @@ - (void)ensureTextCache
    if (!b)
      return;
  
@@ -259,7 +259,7 @@ index 71b6d2e..fd7c520 100644
        && cachedTextStart == BUF_BEGV (b)
        && pt >= cachedTextStart
        && (textLen == 0
-@@ -8122,7 +8237,7 @@ included in the cached AX text (it is handled separately via
+@@ -8170,7 +8285,7 @@ included in the cached AX text (it is handled separately via
      {
        [cachedText release];
        cachedText = [text retain];
@@ -268,7 +268,7 @@ index 71b6d2e..fd7c520 100644
        cachedTextStart = start;
  
        if (visibleRuns)
-@@ -9090,6 +9205,7 @@ - (void)postCompletionAnnouncementForBuffer:(struct buffer *)b
+@@ -9138,6 +9253,7 @@ - (void)postCompletionAnnouncementForBuffer:(struct buffer *)b
    ptrdiff_t currentOverlayStart = 0;
    ptrdiff_t currentOverlayEnd = 0;
  
@@ -276,7 +276,7 @@ index 71b6d2e..fd7c520 100644
    specpdl_ref count2 = SPECPDL_INDEX ();
    record_unwind_current_buffer ();
    if (b != current_buffer)
-@@ -9248,6 +9364,7 @@ - (void)postCompletionAnnouncementForBuffer:(struct buffer *)b
+@@ -9296,6 +9412,7 @@ - (void)postCompletionAnnouncementForBuffer:(struct buffer *)b
        self.cachedCompletionOverlayEnd = 0;
        self.cachedCompletionPoint = 0;
      }
@@ -284,7 +284,7 @@ index 71b6d2e..fd7c520 100644
  }
  
  /* ---- Notification dispatch (main entry point) ---- */
-@@ -9844,6 +9961,10 @@ - (void)dealloc
+@@ -9892,6 +10009,10 @@ - (void)dealloc
  #endif
  
    [accessibilityElements release];
@@ -295,7 +295,7 @@ index 71b6d2e..fd7c520 100644
    [[self menu] release];
    [super dealloc];
  }
-@@ -11293,6 +11414,9 @@ - (instancetype) initFrameFromEmacs: (struct frame *)f
+@@ -11341,6 +11462,9 @@ - (instancetype) initFrameFromEmacs: (struct frame *)f
  
    windowClosing = NO;
    processingCompose = NO;
@@ -305,7 +305,7 @@ index 71b6d2e..fd7c520 100644
    scrollbarsNeedingUpdate = 0;
    fs_state = FULLSCREEN_NONE;
    fs_before_fs = next_maximized = -1;
-@@ -12601,6 +12725,80 @@ - (id)accessibilityFocusedUIElement
+@@ -12649,6 +12773,80 @@ - (id)accessibilityFocusedUIElement
     The existing elements carry cached state (modiff, point) from the
     previous redisplay cycle.  Rebuilding first would create fresh
     elements with current values, making change detection impossible.  */
@@ -386,7 +386,7 @@ index 71b6d2e..fd7c520 100644
  - (void)postAccessibilityUpdates
  {
    NSTRACE ("[EmacsView postAccessibilityUpdates]");
-@@ -12611,11 +12809,59 @@ - (void)postAccessibilityUpdates
+@@ -12659,11 +12857,59 @@ - (void)postAccessibilityUpdates
  
    /* Re-entrance guard: VoiceOver callbacks during notification posting
       can trigger redisplay, which calls ns_update_end, which calls us