Support gitea/forgejo

[newtykip]

Is your feature request related to a problem? Please describe.
Currently, the CLI only supports repositories hosted on GitHub and GitLab. Many of us primarily use Gitea/Forgejo-based git servers, and I think it would be nice for the CLI to support repositories hosted on them.

Describe the solution you'd like
Add support for fetching user information and contributor data from Gitea/Forgejo using its API.

Describe alternatives you've considered
To my knowledge, there is currently no functional workaround.

Additional context
You can fetch a user on a Gitea server by their username using the /users/{username} endpoint (swagger)

Gitea does not explicitly have an endpoint to list all contributors of a repository, however, you can get a paginated list of all commits using the /repos/{owner}/{repo}/commits endpoint (swagger). Perhaps we could fetch all the pages and find all the collaborators using that?

The Forgejo API mirrors that of Gitea.