Use cmake-rn

[kraenhansen]

I wanted to show how I intended the React Native Node-API tooling to be used: cmake-rn taking control of the building of Apple frameworks and construction of the Xcframework.

It builds 🤷 But I haven't tried running it (because I don't know how to 🙈) and I am without a doubt missing context for what I'm suggesting here 😁 Feel free to pick whatever makes sense to the project (if any).

Arguably, you could also move the call to cmake-rn all the way out to the package.json as a package script, like we do in the host when building weak-node-api.

Note: This is currently missing linking with weak-node-api as per https://github.com/callstackincubator/react-native-node-api/tree/main/packages/cmake-rn#linking-against-node-api

# Defines the "weak-node-api" target
include(${WEAK_NODE_API_CONFIG})
target_link_libraries(addon PRIVATE weak-node-api)

☝️ is because callstackincubator/react-native-node-api#192 causing weak-node-api to miss an x86_64 slice.