Optional subclassing of MetroViewModelFactory

[adamdanielczyk]

Following up on #1497 - I've also recently migrated my project to Metro and so far so good, but wondered if it would make sense to have a default implementation for MetroViewModelFactory delivered by metrox-viewmodel library? Isn't it the case that most of use cases will copy-paste this exact MyViewModelFactory snippet from docs?

https://zacsweers.github.io/metro/latest/metrox-viewmodel/#metroviewmodelfactory

@Inject
@ContributesBinding(AppScope::class)
@SingleIn(AppScope::class)
class MyViewModelFactory(
  override val viewModelProviders: Map<KClass<out ViewModel>, Provider<ViewModel>>,
  override val assistedFactoryProviders: Map<KClass<out ViewModel>, Provider<ViewModelAssistedFactory>>,
  override val manualAssistedFactoryProviders: Map<KClass<out ManualViewModelAssistedFactory>, Provider<ManualViewModelAssistedFactory>>,
) : MetroViewModelFactory()

[ZacSweers]

It's not a given that every project will use that exact AppScope key or wants to use this exact implementation

[adamdanielczyk]

Fair enough, perhaps I looked at this from the perspective of my playground app where only AppScope is used