Add pixi

[maresb]

With this you can

pixi run init-jupyter-kernel
pixi shell
jupyter lab

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Side note:

I'm working on a guide for migrating to pixi, and a tool to do it automatically via conda-lock.

The guide is here: https://github.com/conda/conda-lock/pull/708: (preview)

Note that because things are unreleased, to follow the guide you need to install conda-lock via

pipx install --force git+https://github.com/conda/conda-lock@main

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📚 Documentation preview 📚: https://causalpy--412.org.readthedocs.build/en/412/

[codecov[bot]]

Codecov Report

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

Project coverage is 94.40%. Comparing base (66c2623) to head (c12df48). Report is 6 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #412      +/-   ##
==========================================
+ Coverage   94.35%   94.40%   +0.05%     
==========================================
  Files          30       31       +1     
  Lines        1967     1985      +18     
==========================================
+ Hits         1856     1874      +18     
  Misses        111      111              

:umbrella: View full report in Codecov by Sentry.
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[maresb]

I should add @aseyboldt's CUDA stuff here too. But that shouldn't block us from reviewing the rest of this.