Refactor Tests to a Dedicated `tests/` Folder.

[AkshayAwate]

Currently, the codebase does not have a dedicated tests/ folder. All the tests are included within the main code itself. We may consider refactoring to move the tests into a separate folder for better structure and maintainability. What do you think ? @dbieber

[saurabhrane1199]

I second this, just makes the library code more readable

[akp111]

In favour of it