feat(`foundry-lock`): expose lockfile structure/parsing in public crate

[beeb]

Component

Forge

Describe the feature you would like

In Soldeer, we would like to be able to parse foundry.lock files so that we can recursively install subdependencies of packages even if they use git submodules themselves.

To do this efficiently, it would be of great help if we could parse the foundry.lock file to know which commit to checkout for git submodules, even in the absence of a .git folder (which is usually omitted from packaged dependencies).

I started to look into vendoring the lockfile module into Soldeer, but it would be a lot of work and I'd have to keep it in sync with any changes upstream, which is bad.

Is there a chance that foundry could extract the logic related to parsing the lockfile into a separate crate which gets published on crates.io? This is because we publish soldeer on there and we can't use git dependencies. I'd love to be able to re-use the logic used internally by forge.

Ideally, the crate would pull in minimal dependencies to avoid bloating soldeer.

Additional context

mario-eth/soldeer#346