Improve BitmapUtils: Bitmap Handling and Image Processing for Modern APIs and Performance Enhancements

[Onkar755]

This PR introduces several improvements and optimizations across bitmap and image processing functions, addressing issue #13617 :

1. Bitmap Decoding Update: Introduced ImageDecoder for Android 9 (API 28) and above, while maintaining backward compatibility with BitmapFactory for older versions.
2. Refactor rotateImage(): Improved EXIF orientation handling and clarified code for readability.
3. Refactor usernameToColor: Improved MD5 validation, optimized color generation, and enhanced code readability for better performance.

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Testing

• All existing unit and instrumented tests were run and passed successfully.

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• Please review the changes.
• If needed, additional tests can be added based on review feedback.
• Any suggestions or improvements are welcome as this is my first contribution to this repository.

This PR aligns with the contribution guidelines and addresses the issue as described.

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