I couldn't find any documentation on using RevenueCat bindings in Xamarin Forms, or any examples. How to get started? I think it's supposed to be obvious, but it wasn't for me.
Answering my own question below, I've made a small start, haven't tested any code yet. Please feel free to expand or correct.
This is for Xamarin Forms iOS on Visual Studio 2022 for Mac; MAUI could be similar.