Errors should be publicly exported

[qdm12]

Right now errors are in the internal directory. That means a repository importing this one cannot import those error variables and thus cannot check the error with errors.Is(err, ErrXYZ).

One could move errors to their own errors package in pkg/errors or have them locally defined for each exported package.

[mikelodder7]

Thanks for this. We can move them or we accept PRs to make the change.