feat(iOS): Add split screen support

[tboba]

Description

This PR adds the ability to create split screen on iOS apps.
Currently in PoC state!

Changes

Test code and steps to reproduce

Checklist

• Included code example that can be used to test this change
• Updated TS types
• Updated documentation:
  • https://github.com/software-mansion/react-native-screens/blob/main/guides/GUIDE_FOR_LIBRARY_AUTHORS.md
  • https://github.com/software-mansion/react-native-screens/blob/main/native-stack/README.md
  • https://github.com/software-mansion/react-native-screens/blob/main/src/types.tsx
  • https://github.com/software-mansion/react-native-screens/blob/main/src/native-stack/types.tsx
• Ensured that CI passes

[sidorchukandrew]

🎉🎉🎉

[flodlc]

Hi @tboba, great to see this PR exists ! Is it still on progress ? Can't wait to test it !!

[tboba]

@flodlc As in react-native-screens our main focus for now is to improve Fabric experience for users, I had to postpone working on this PR for another week or two, but I promise we'll come back on working on this!