fix: support prefer cross-fade transitions in useAnimatedKeyboard

On iOS, when Prefer Cross-Fade Transitions is enabled, the keyboard
position and height is reported differently (0 instead of Y position
value matching height of the frame.) Override the initial and target
keyboard height when this preference is enabled.

packages/react-native-reanimated/apple/reanimated/apple/keyboardObserver/REAKeyboardEventObserver.mm

@@ -201,6 +201,17 @@ - (void)keyboardWillChangeFrame:(NSNotification *)notification
   _initialKeyboardHeight = windowSize.height - beginFrame.origin.y;
   _targetKeyboardHeight = windowSize.height - endFrame.origin.y;
 
+  bool prefersCrossFade = false;
+#if __has_include(<UIKit/UIAccessibility.h>)
+  prefersCrossFade = UIAccessibilityPrefersCrossFadeTransitions();
+#endif
+  if (prefersCrossFade && beginFrame.origin.y == 0) {
+    _initialKeyboardHeight = 0;
+  }
+  if (prefersCrossFade && endFrame.origin.y == 0) {
+    _targetKeyboardHeight = 0;
+  }
+
   /*
     This may seem a bit confusing, but usually, the state should be either OPENED or CLOSED.
     However, if it shows as OPENING, it means that the interactive dismissal was canceled.