Refactor note use cases and remove platform-specific audio player implementation

- Removed the platform-specific `platformModule` and `PlatformAudioPlayer` interface.
- Updated note use case interfaces to use a consistent naming convention (`UseCaseContract`).
- Refactored dependency injection in `Modules.kt` to use concrete implementations instead of interfaces for note use cases.
- Adjusted ViewModel and service classes to accommodate changes in use case implementations.
- Cleaned up unused imports and removed iOS-specific audio validation and player classes.
- Updated tests to reflect changes in the note use case implementations and audio player references.

Author: close-hall