fix: contributors and committers section missing

Resolves part of #606 (closed)

Also includes a minor refactor. The MR extracts the Contributor and Committer cards into their own components. This extraction is needed to make this work with the <Protected> component, which handles authentication and authorization.

As an added benefit, componentizing the Contributor and Committer cards allows us to encapsulate their data-fetching and rendering logic.

The same could be done with CBI, but it is out of scope.

However, there is quite a bit of duplication between these two cards. I think this can be improved upon in the future.