Add support for multi-workspace hack?

[LHolten]

At $work we have a project with multiple cargo workspaces. We would like to unify the dependency features between all the crates in all of these workspaces. Is that something that Hakari could support?

This would be especially useful in combination with a fix for rust-lang/rust-analyzer#18804, because that would let us find all references of functions/types across workspaces!

I can help implement this feature, although I am not yet familiar with this code base.