chore: implement HostPlatformTouch

[Saadnajmi]

Note: as it stands this doesn't work, as the c++ infrastructure is still using BaseTouch for some reason 🤷

Summary:

Move our diffs from BaseTouch to HostPlatformTouch

Test Plan:

Added this code to RNTesterPlayground to see if the desktop specific keys were passed:

<Pressable
  style={styles.pressable}
  onTouchStart={event => {

    console.log('Playground onPress event:', event.nativeEvent.metaKey);
  }}>
    <RNTesterText>Press here to log the press event</RNTesterText>
</Pressable>

[Saadnajmi]

Closing as this doesn't work.