Moved older descriptor, calculator, loss to legacy + tests fixed

[ipcamit]

Summary

• This commit moves the descriptor, loss and calculator object to legacy module.
• Fixed the tests so that all tests pass now.
• Bumped version to 1.0.0

This should finish all the development. Now only documentation, examples, and Readme remains, that I will fix in comping week.

Checklist

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• Make sure your code is properly formatted. isort and black are used for this purpose. The simplest way is to use pre-commit. See instructions here.
• Doc strings have been added in the Google docstring format on your code.
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• Tests have been added for any new functionality or bug fixes.
• All linting and tests pass.

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