Add Data Format Converter

[aknierim]

Adds a data converter class that allows conversion between data formats for pyvisgen.

With this we can skip doing simulations over and over to get the same data in different formats, thus saving us many hours (e.g. ~20 min of conversion vs ~25h of new simulations).

To-Do

• PT support
• Docstrings & type hints
• Docs pages
• CLI tool
• Tests
• Changelog

Note: I don't plan to include FITS for now, until we have fixed our FITS writer. Once that is taken care of, we can add FITS conversion, too.

Note 2: Draft for now until I have added the items from the To-Do list.

Merge after #134

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 95.67%. Comparing base (6c80d86) to head (409eb58).
✅ All tests successful. No failed tests found.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #132      +/-   ##
==========================================
- Coverage   96.20%   95.67%   -0.53%     
==========================================
  Files          32       25       -7     
  Lines        2002     1619     -383     
==========================================
- Hits         1926     1549     -377     
+ Misses         76       70       -6     

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