[SDK] Update authenticate to handle OAuth cancel error

Should return the cancel error when authorization return `error=cancel` after `authenticate`. It is worth adding to all the SDKs, but we can add it to the native SDKs first.

- [X] iOS
- [X] Android
- [ ] React-native
- [ ] Flutter
- [ ] Xamarin

Start at the authenticate flow in the React Native, Flutter, and Xamarin SDKs and trace how the authorization return value handles error=cancel. Implement the remaining SDK behavior so authenticate returns the cancel error, then verify each unchecked SDK’s cancellation path; iOS and Android are already marked complete.

Written by the indexing model from the issue text.