refactor: deprecations clean up

[lukewalczak]

Changes

This PR updates the documentation to reflect the removal of Material Design 2 (MD2) support and standardizes theme naming conventions across the codebase. The changes focus on simplifying the theming system and providing clearer guidance for users.

1. Theme Naming Standardization

• Replaced MD3LightTheme and MD3DarkTheme with LightTheme and DarkTheme respectively
• Updated all code examples to use the new theme naming convention
• Removed references to MD2/MD3 versioning in theme configuration

2. Documentation Cleanup

• Removed the entire "Material Design 2" section from the theming guide
• Removed MD2-specific code examples and configuration options
• Updated theme property documentation to remove version-related properties
• Simplified theme configuration examples to focus on the current theming system

3. React Navigation Integration

• Removed React Navigation directory and package along with integration examples and related code

4. @deprecated and @reanamed annotations

• Removed deprecated annotations and renamed component annotations

[github-actions]

The mobile version of example app from this branch is ready! You can see it here.

[callstack-bot]

Hey @lukewalczak, thank you for your pull request 🤗. The documentation from this branch can be viewed here.