Introduce UI State models

[yschimke]

Avoid using dataAssertNoErrors. Instead have a model with Loading, Success, Error.

Follow up work to improve errors and loading.

[martinbonnin]

Very cool 👍

Avoid using dataAssertNoErrors

FWIW, I'm not super happy with this dataAssertNoErrors and with error handling in general.
It's not easy because of partial data and stuff like "GraphQL errors returning 200" but we put some thoughts over there: apollographql/apollo-kotlin#4711

[yschimke]

+1 to making errors just another state. Not sure what I want, but some random thoughts.

I'm not sure what I want, but I think something like https://github.com/skydoves/sandwich, with an additional Loading state would work really well for Compose screens.

We found this section abstraction for screens useful.

https://github.com/google/horologist/blob/9cb3879ed6b044f702b2b2ad0de06f92e5985a09/sample/src/main/java/com/google/android/horologist/sectionedlist/stateful/SectionedListStatefulScreen.kt#L118-L151

Might be useful if you a screen built from multiple queries, each of which has Loading/Success/Failed states.