Move from setup.py to pyproject.toml

[phoebe-p]

• Move from setup.py to pyproject.toml
• Use hatchling build system instead of setuptools
• use uv pip install in CI workflows (~30 x faster than pip install)

[codecov]

Codecov Report

Attention: Patch coverage is 88.24020% with 141 lines in your changes missing coverage. Please review.

Project coverage is 86.27%. Comparing base (3eec1fb) to head (8f6ae3c).
Report is 1 commits behind head on analytical_RT.

Files	Patch %	Lines
rayflare/ray_tracing/rt_structure.py	85.50%	90 Missing ⚠️
rayflare/ray_tracing/rt_common.py	86.30%	40 Missing ⚠️
rayflare/ray_tracing/rt_matrix.py	96.02%	11 Missing ⚠️

Additional details and impacted files

@@                Coverage Diff                @@
##           analytical_RT      #73      +/-   ##
=================================================
- Coverage          86.64%   86.27%   -0.38%     
=================================================
  Files                 21       23       +2     
  Lines               3805     3832      +27     
=================================================
+ Hits                3297     3306       +9     
- Misses               508      526      +18     

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