useXRInportSourceState fails to update when hand exit view, built-in hand are duplicated.

[geyang]

To reproduce:

1. on the vision pro, open the first example on this page (the room): https://pmndrs.github.io/xr/docs/getting-started/examples
2. move your hand out of view, then back. A second hand instance shall appear, frozen at the last location where the hand existed tracking range.

Now, if you call useXRInputSource("hand", "left"), the post.data array remains unchanged since VisionPro lost tracking.

[bbohlender]

@geyang, thank you for reporting. I will investigate. Unfortunately, I cannot debug because I don't own a Vision Pro. Will contact you once I think I found a resolution so you can confirm, if thats possible :)

[geyang]

I made a custom Hand component this morning that resolves this issue for our production system. Not sure why the useXRInputSource hook is providing stale states though. The bug remains.