Adding uv to the Github CI and requirements to pyproject

[emlynsg]

This PR uses uv instead of pip in the nox routine for CI tests.
To adhere to the requirements of uv, it also includes a uv.lock file locking dependencies for CI reproducibility, and has merged requirements into the pyproject.toml file in line with PEP best practice (https://packaging.python.org/en/latest/specifications/pyproject-toml/).
The installation process remains the same with this change.
My understanding is that dependabot will work as-is with the same configuration.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 88.09%. Comparing base (c7d462a) to head (febe2ea).

Additional details and impacted files

@@           Coverage Diff           @@
##           master     #452   +/-   ##
=======================================
  Coverage   88.09%   88.09%           
=======================================
  Files          44       44           
  Lines        6449     6449           
=======================================
  Hits         5681     5681           
  Misses        768      768           

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