Replace the RootScreen nav stubs with a real NavHost. Each destination
binds its existing M1 ViewModel from route args.
- ui/navigation: Dest route table (string-based; no serialization plugin)
+ FloretNavHost (lists -> task list -> detail / edit).
- Base scaffolds for TaskListScreen, TaskDetailScreen, TaskEditScreen,
wired to their ViewModels — skeletons for the rich M2/M3 UI.
- RootScreen READY branch now hands off to FloretNavHost.
- Add navigation-compose 2.9.0; supporting strings.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>