Unable to move the thumb position from outside the slider when having a custom thumbImage

## Environment

* react-native info output:
```
// react-native info
Expo v53
```

* are you using the new architecture?
yes

* which version of react & react-native are you using?
React 19 and React Native v0.79.2

## Description

When having a custom thumbImage, the position of the thumb is not able to be updated from outside the Slider. For example, if you have a useEffect that change the value of the slider, the thumb position is being moved when thumbImage is by default. However, with a custom thumbImage, it's not the case.

## Reproducible Demo

If you have something like this, clicking the button should move well the thumb position to position 0:
```
const [value, setValue] = useState(20)
return (
<>
setValue(0)}
/>



)
```

However, if you add a custom thumbImage, when clicking the button, the thumb position does not go to position 0:
```
const [value, setValue] = useState(20)
return (
<>
setValue(0)}
/>

}
thumbTintColor={'#62A6E4'}
thumbImage={require('@src/assets/images/SliderThumb.png') as ImageURISource}
/>

)
```

Start by reproducing the controlled Slider example with a custom thumbImage and compare it with the default thumb behavior. Trace how external value changes are applied when thumbImage is set; done means pressing the button moves the custom thumb to position 0 as it does without a custom image.

Written by the indexing model from the issue text.