ci: Switch from hatch, pip to uv in GitHub Actions

[dangotbanned]

Closes #3718

One step towards #3577

This PR moves to uv in each of:

• build.yml
• docbuild.yml
• lint.yml

I tried this a while back, but gave up on (27999c1).
Since then, I've used uv some more as I mentioned in (#3577 (comment)) - which helped unblock this part 😅

[mattijn]

Great PR @dangotbanned! Do you have a reference why this is environment definition is necessary? Thanks!

[dangotbanned]

Thanks @mattijn!
Yeah I can explain.

I've enabled UV_SYSTEM_PYTHON as a workflow environment variable to add the --system argument on all relevant uv commands.
You can see in narwhals/.github/workflows/downstream_tests.yml that argument is used 25 times.

So this is just to keep it simple, making sure it is there when needed - but isn't something you need to worry about if updating the workflow in the future 🙂

[mattijn]

Regarding feedback on parallel running of sphinx docs:

WARNING: the sphinxext_altair.altairplot 
extension does not declare if it 
is safe for parallel reading, 
assuming it isn't - please ask 
the extension author to check 
and make it explicit

Is this something worthwhile pursuing for?

[dangotbanned]

Regarding feedback on parallel running of sphinx docs:

WARNING: the sphinxext_altair.altairplot 
extension does not declare if it 
is safe for parallel reading, 
assuming it isn't - please ask 
the extension author to check 
and make it explicit

Is this something worthwhile pursuing for?

@mattijn

It has the potential to speed this CI job up, but I think I'd struggle with testing --jobs locally:

This feature only works on systems supporting “fork”. Windows is not supported.

I'm happy to support if anyone else wants to take the lead on it though.
I just imagine getting it working on native posix will be easier than wsl or MINGW64

---

I really need to transition away from windows at some point 😔
Think it is causing problems in vega/vega-datasets#648 (comment) as well

[mattijn]

Thanks for providing context regarding the environment variable of uv!

In fact I'm quite happy that we have maintainers on multiple operating systems as it increase the robustness of the codebase.