chore: update code base for Python 3.13 ; add uv migration and make it compatible with pyodide 2024, used by Marimo

[chabotsi]

Hello there,

This PR bundles a series of updates to modernize the codebase and improve compatibility:

Changes

Compatibility Updates

• Removed numexpr dependency for full pyiodide compatibility
• Updated np.trapz → np.trapezoid (numpy API change)
• Migrated from scipy.stats.mvn to scipy.stats.multivariate_normal
• Fixed crash in download_data with Python 3.14 and numpy/xarray when opening files
• Updated dependency versions for marimo wasm compatibility

Bug Fixes

• Fixed censgaussfit to handle positive semi-definite sigma matrices
• Updated tests to check values instead of dtypes
• Set fixed random seed for reproducible tests

Packaging & Tooling

• Moved config.ini into the package for distribution
• Migrated project to uv package manager
• Updated version to 2.0.0

Code Quality

• Applied black formatting

Testing

All tests pass with the updated dependencies and Python 3.13.

The chosen versions are compatible with Pyodide 2024, used by Marimo to make WASM applications.

[NRaillard]

Hi @chabotsi,
Thanks for this PR.
Would it be possible to update the CICD to use the latest versions of the actions and adapt to uv also the documentation?
Thanks,
Nicolas.