[iOS] Preserve disabled button targets under box-none parents (#4506)

## Description

Follow-up to #4495.

When an RNGH `Touchable`/`Pressable` uses `pointerEvents="box-none"`, a
disabled
RNGH button returned from one of its child hit tests is rejected by
`shouldHandleTouch:` because `userEnabled` is false.

The `box-none` branch then continues checking lower siblings, which
allows an
enabled sibling underneath the disabled control to receive the touch.

This is inconsistent with the behavior preserved in #4495, where a
disabled
button can still remain the hit target so controls underneath don't take
over
the touch, while the disabled button itself doesn't activate.

The `box-none` path now preserves `RNGestureHandlerButton` child hits
instead
of discarding them based on their enabled state.

## Device observations

Reproduced on iOS with both RNGH `Touchable` and RNGH `Pressable`.

With an RNGH parent using `pointerEvents="box-none"`:

- tapping the disabled foreground triggers the enabled sibling
underneath
- tapping the exposed background also triggers the background, as
expected

Changing only the parent to a React Native `View` with the same
`pointerEvents="box-none"`:

- tapping the disabled foreground does nothing
- tapping the exposed background triggers the background

<details>
<summary>Test example</summary>

```tsx
import React, { useState } from 'react';
import {
  Pressable as RNPressable,
  StyleSheet,
  Text,
  View,
} from 'react-native';
import {
  Pressable as RNGHPressable,
  Touchable,
} from 'react-native-gesture-handler';

type ButtonType = 'touchable' | 'pressable';

export default function BoxNoneDisabledTargetExample() {
  const [buttonType, setButtonType] = useState<ButtonType>('touchable');
  const [useRNParent, setUseRNParent] = useState(false);
  const [backgroundPresses, setBackgroundPresses] = useState(0);

  const Button =
    buttonType === 'touchable'
      ? Touchable
      : RNGHPressable;

  const children = (
    <>
      <Button
        onPress={() => setBackgroundPresses((count) => count + 1)}
        style={[StyleSheet.absoluteFillObject, styles.background]}>
        <Text>Enabled background</Text>
      </Button>

      <Button
        disabled
        style={styles.disabledForeground}>
        <Text>Disabled foreground</Text>
      </Button>
    </>
  );

  return (
    <View style={styles.container}>
      <RNPressable
        onPress={() =>
          setButtonType((current) =>
            current === 'touchable' ? 'pressable' : 'touchable'
          )
        }>
        <Text>Button type: {buttonType}</Text>
      </RNPressable>

      <RNPressable onPress={() => setUseRNParent((value) => !value)}>
        <Text>
          Parent: {useRNParent ? 'React Native View' : 'RNGH button'}
        </Text>
      </RNPressable>

      {useRNParent ? (
        <View pointerEvents="box-none" style={styles.frame}>
          {children}
        </View>
      ) : (
        <Touchable pointerEvents="box-none" style={styles.frame}>
          {children}
        </Touchable>
      )}

      <Text>Background presses: {backgroundPresses}</Text>
    </View>
  );
}

const styles = StyleSheet.create({
  container: {
    padding: 16,
    gap: 12,
  },
  frame: {
    height: 150,
  },
  background: {
    backgroundColor: '#9fd8a8',
    justifyContent: 'flex-end',
    padding: 8,
  },
  disabledForeground: {
    position: 'absolute',
    left: 40,
    right: 24,
    top: 20,
    height: 85,
    backgroundColor: '#9a9a9a',
    alignItems: 'center',
    justifyContent: 'center',
  },
});
```

</details>

## Test plan

Test on a physical iOS device with both RNGH `Touchable` and RNGH
`Pressable`.

For each component:

1. Use an RNGH parent with `pointerEvents="box-none"`.
2. Tap well inside the disabled foreground.
3. Verify the enabled background does **not** receive `onPress`.
4. Tap the exposed background area.
5. Verify the background does receive `onPress`.
6. Replace only the parent with a React Native `View` using
   `pointerEvents="box-none"` and repeat.

Expected:

| Parent | Disabled foreground | Exposed background |
| --- | --- | --- |
| RNGH `box-none` parent | no press | background press |
| RN `View` `box-none` parent | no press | background press |

Before this change, the RNGH-parent case incorrectly sends the disabled
foreground tap to the background sibling.

## AI assistance

Used AI to help inspect the surrounding hit-test paths and prepare the
test
case and patch. I personally reproduced the issue on device.

Author: rileysay

packages/react-native-gesture-handler/apple/RNGestureHandlerButton.mm

@@ -1454,7 +1454,8 @@ - (BOOL)shouldHandleTouch:(RNGHUIView *)view atPoint:(CGPoint)point
 {
   if ([view isKindOfClass:[RNGestureHandlerButton class]]) {
     RNGestureHandlerButton *button = (RNGestureHandlerButton *)view;
-    return button.userEnabled;
+    return button.userEnabled && button.pointerEvents != RNGestureHandlerPointerEventsBoxNone &&
+        button.pointerEvents != RNGestureHandlerPointerEventsNone;
   }
 
   // Certain subviews such as RCTViewComponentView have been observed to have disabled
@@ -1501,7 +1502,9 @@ - (RNGHUIView *)hitTest:(CGPoint)point withEvent:(UIEvent *)event
       if (!subview.isHidden && subview.alpha > 0) {
         CGPoint convertedPoint = [subview convertPoint:point fromView:self];
         UIView *hitView = [subview hitTest:convertedPoint withEvent:event];
-        if (hitView != nil && [self shouldHandleTouch:hitView atPoint:point]) {
+        if (hitView != nil &&
+            ([hitView isKindOfClass:[RNGestureHandlerButton class]] ||
+             [self shouldHandleTouch:hitView atPoint:point])) {
           return hitView;
         }
       }