Migrate from package extras to dependency groups

[hugovk]

Instead of pip install -e .[tests] run pip install -e --group tests.

Similarly with uv pip install.

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 100.00%. Comparing base (ba91665) to head (05dfe49).

Additional details and impacted files

@@            Coverage Diff            @@
##              main      #223   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files            2         2           
  Lines           16        16           
=========================================
  Hits            16        16           

Flag	Coverage Δ
macos-latest	100.00% <ø> (ø)
ubuntu-latest	100.00% <ø> (ø)
windows-latest	100.00% <ø> (ø)

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