Support uv as an alternative to pip

[txchen]

Is your feature/enhancement proposal related to a problem? Please describe.

uv https://github.com/astral-sh/uv is extremely fast to install pip libs, it would be nice if pdm (install/sync) can optionally invoke uv instead of pip to make it faster.

Describe the solution you'd like

Add a pip backend option, and support uv.

[frostming]

There isn't pip in the backend.

We'll see if lockfile format can be standardized and only then we can consider uv.

[ericjmorey]

What does it mean to standardize a lock file?

[frostming]

The community and packaging team is making effort on this: https://discuss.python.org/t/lock-files-again-but-this-time-w-sdists/46593

[Mjboothaus]

Maybe a pdm-uv package/extension-- keep up the excellent work