feat: support for VisionOS

[j6alvarez]

I have been doing some work with this repo https://github.com/callstack/react-native-visionos

And wanted to contribute sharing what made it work for me following the instructions in this post

This allows to run appleAuth methods for react-native-visionos

Fixes #350

[CLAassistant]

All committers have signed the CLA.

[mikehardy]

This seems reasonable, the only imaginable way it could fail is if the UIKit import isn't available on other platforms, but I just scanned other repos I maintained and I don't see them IFDEF'ing the UIKit.h import even though I'm certain they build on macCatalyst at least, and I believe macos even.

Either way, that's easy to fix either. Happy to merge this for visionOS support now

[mikehardy]

😆 indeed when I ran yarn example:macos what I feared happened - the build was broken for macOS because of the UIKit.h inclusion. I swear I had seen that somewhere but also I checked and couldn't find it.

Anyway, one quick change later and it's good

#if TARGET_OS_IPHONE
#import <UIKit/UIKit.h>
#endif

[j6alvarez]

Uh nice that you fixed it easily, I haven't use the library for macOS, just for visionOS and iOS. Thanks for fixing this 🙏🏽