Parse `dist-workspace.toml` for version (#17868)
Extends https://github.com/astral-sh/ruff/pull/17866, using
`dist-workspace.toml` as a source of truth for versions to enable
version retrieval in distributions that are not Git repositories (i.e.,
Python source distributions and source tarballs consumed by Linux
distros).
I retain the Git tag lookup from
https://github.com/astral-sh/ruff/pull/17866 as a fallback — it seems
harmless, but we could drop it to simplify things here.
I confirmed this works from the repository as well as Python source and
binary distributions:
```
❯ uv run --refresh-package ty --reinstall-package ty -q -- ty version
ty 0.0.1-alpha.1+5 (2eadc9e61 2025-05-05)
❯ uv build
...
❯ uvx --from ty@dist/ty-0.0.0a1.tar.gz --no-cache -q -- ty version
ty 0.0.1-alpha.1
❯ uvx --from ty@dist/ty-0.0.0a1-py3-none-macosx_11_0_arm64.whl -q -- ty version
ty 0.0.1-alpha.1
```
Requires https://github.com/astral-sh/ty/pull/36
cc @Gankra and @MichaReiser for review.