🚀: Add support for State to UiState mapper

[HGilman]

Description

I like to separate State and UiState which contains strings, colors, and so on. To make this mapping we need to have reference to context. When we subscribe to state we could pass uiMapper with current context (LocalContext.current in case of Compose, or just context in case of fragments).

[Nek-12]

Hi, I need to think about this to see if we'd be actually introducing an architectural antipattern.

Interacting with frameworks and platform SDKs is the responsibility of the UI layer - FlowMVI only maintains a minimal integration with UI frameworks.

Mapping state -> resource should ideally happen in composition at the usage site:

enum class GreetingType { Morning, Day, Evening }

val state by store.subscribe()
val uiState = mapToUiState(state) // ❌ too early and wasted resources

HomeScreen(uiState)

/// 

val state by store.subscribe()
HomeScreenContent(state)

fun HomeScreenContent(state: State) {
    Text(text = stringResource(state.greetingType.mapToResourceId())) // ✅ correct at usage site
}

My questions:

1. Why do you want to map not at the usage site, but rather at subscription site?
2. How would the implementation in FlowMVI be different from a simple State.toUiState() function?
3. Any example code?