ENH: add tool.meson-python.wheel.exclude setting

[dnicolodi]

I am not entirely sure we want to include this facility: it may potentially be abused when better solutions exist. However, I think it is better than the solution we currently recommend https://mesonbuild.com/meson-python/how-to-guides/shared-libraries.html#shared-library-from-subproject of adding specific options to subprojects to exclude this or that parts from the installation.

[dnicolodi]

Another idea I was toying with is to extend the filtering by meson install tags to allow to specify different tags per subproject. meson-python does not rely on the meson implementation of the filtering anyway, thus extending the facility is possible.

[rgommers]

Thanks @dnicolodi! I like this. Agreed that these unmappable install locations/targets are a pain point, and this is a nice and ergonomic solution I think.

The wheel.exclude name is good, and it matches the name in scikit-build-core which is helpful.

One question about using introspection metadata locations. I can see that working, but there's also an alternative of using wheel locations - I'm not quite sure which is better.

[rgommers]

typo dubproject

[rgommers]

It'd be fine to support this for meson>=1.3.0 only I think.

[rgommers]

Another idea I was toying with is to extend the filtering by meson install tags to allow to specify different tags per subproject. meson-python does not rely on the meson implementation of the filtering anyway, thus extending the facility is possible.

That may still require changes to the subproject itself (e.g., there are multiple shared libraries and you need only one of them), so is less general. I prefer wheel.exclude because of that.

[dnicolodi]

We could also consider implementing both wheel.exclude and wheel.include so that the first could be used to exclude a whole subtree and the latter to include selected files in the same subtree.

[rgommers]

We could also consider implementing both wheel.exclude and wheel.include so that the first could be used to exclude a whole subtree and the latter to include selected files in the same subtree.

I can see the appeal of that, yes. Especially on projects with lots of install targets, that seems nice. Although the cases where you can't make things concise with excluding install tags + wheel.exclude may be a small minority.

This could be done immediately, or later if there's demand. Given this PR is very nice and clean, may be okay to add it immediately?