Add a GitHub Action to release to PyPI

[brianhelba]

While it's possible to build this project by installing directly from Git, this makes it more difficult for downstream users to strictly version this package. Worse, the usage of Git LFS isn't supported by all package managers (though it is supported by uv as a very recent feature).

I think adding this infrastructure to publish automatically to PyPI upon the creation of a GitHub Release shouldn't be too burdensome, and it'll likely save a lot of hassles for downstream consumers of this package in the long run.

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To set up PyPI, see: https://docs.pypi.org/trusted-publishers/creating-a-project-through-oidc/

You'll need to set:

PyPI Project Name: uvdat-flood-sim
Owner: OpenGeoscience
Repository name: uvdat-flood-sim
Workflow name: release.yml
Environment name: <empty>

[annehaley]

I asked August about this and he is on board with publishing to PyPI. I have created the pending trusted publisher on my PyPI account. I will make a follow-up PR to update the README once this is merged.