[iOS] Exploring MVI framework for Kotlin Multiplatform, part 5

The longest stream I've done and one of the toughest. Tackling lots of different concepts and challenges.

From a high level, I implemented the MVI renderer for TodoList and navigation to the TodoDetails screen with NavigationLink.

Details here: https://github.com/arkivanov/MVIKotlin/issues/18#issuecomment-609092964