Replace Either with Kotlin Result and optimize ListUtils

[cbeyls]

Using Either<Throwable, T> is basically the same as Result<T> with a less friendly API. Futhermore, Either is currently only used in a single component.

• Replace Either with Result in AccountsInListFragment and AccountsInListViewModel.
• Add a method to convert a NetworkResult to a Result in AccountsInListViewModel. Alternatively, NetworkResult could be used everywhere in the code but other classes are already using Result.
• Replace updateState() method with MutableStateFlow.update() in AccountsInListViewModel.
• Store the current search query in a MutableStateFlow collected by a coroutine. This allows automatically cancelling the previous search when a new query arrives, instead of launching a new coroutine for each query which may conflict with the previous ones.
• Optimize ListUtils.

[connyduck]

The whole account list component is due for a rewrite (move to new package structure, ViewModel & AndroidX paging), I wanted to tackle that soon, but if you want you can do it as well

[cbeyls]

The whole account list component is due for a rewrite (move to new package structure, ViewModel & AndroidX paging), I wanted to tackle that soon, but if you want you can do it as well

I can help. This branch can be used as a starting point too.

[connyduck]

Yes, let's merge this