Add proper pyproject.toml and update outdated dependencies

[lukasjuhrich]

This allows for simple setup via uv pip install -e . --group dev or eventually even uv sync.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 31.78%. Comparing base (a81ea7d) to head (58fb11e).

Additional details and impacted files

@@             Coverage Diff             @@
##           develop     #517      +/-   ##
===========================================
- Coverage    31.81%   31.78%   -0.03%     
===========================================
  Files           70       70              
  Lines         7299     7299              
===========================================
- Hits          2322     2320       -2     
- Misses        4977     4979       +2     

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