1ad6aa8a23
Pubgrub got a new feature where all unavailability is a custom, instead of the reasonless `UnavailableDependencies` and our custom `String` type previously (https://github.com/pubgrub-rs/pubgrub/pull/208). This PR introduces a `UnavailableReason` that tracks either an entire version being unusable, or a specific version. The error messages now also track this difference properly. The pubgrub commit is our main rebased onto the merged https://github.com/pubgrub-rs/pubgrub/pull/208, i'll push `konsti/main-rebase-generic-reason` to `main` after checking for rebase problems.