Support `egg-info` distributions in `find_distributions_in_venv`

[baszalmstra]

Many conda packages (even recent ones) are still using egg-info directories for example:

https://conda.anaconda.org/pytorch/noarch/botorch-0.9.5-0.tar.bz2

We should be able to discover them when they are installed in a Conda environment. This most likely requires changing the Distribution struct a little too to be able to distinguish between dist-info and egg-info installed distributions.

[baszalmstra]

Ive started working on this! :)

[tdejager]

We also have a problem where we cannot actually build the source distributions, support for it would be nice was already requested by a pixi user.

Try:

cargo r mamba-ssm