Support for PEP 735 (dependency groups)

[nathanjmcdougall]

Is your feature request related to a problem? Please describe.

As of uv v0.4.27, the way of declaring dev dependencies is no longer via the [tool.uv.dev-dependencies] section, and this will raise warnings in due course, in favour of the new PEP 735 standard for non-build dependencies.

Describe the solution you would like

For uv users (and others?) support reading the [dependency-groups] map in pyproject.toml to determine dev dependencies.

Additional context

This is relevant for rye support #629.

[nathanjmcdougall]

I sometimes can't believe how poor the GitHub Issues search is (or my ability to use it correctly??). Sorry for the dupe of #885.