MLECO-6390: Refactor UI to remove redundant multiple app screen navigation
- Files have been refactored to be configured for just a single screen
- Redundant Navigation files have been deleted
- All references to navigation in composables and tests have been removed
- Tests have been refactored to use ScreenScaffold to build main screen
Signed-off-by: Olawole Abayomi-Owodunni olawole.abayomi-owodunni@arm.com Change-Id: I5fabd48b6256b5f0476d24b6542c1bca179e4498