GitLab (and other code hosting platform) Support

[chbrown13]

This project currently only evaluates GitHub repositories with the PyGithub library, however many open-source repositories are hosted on other platforms such as GitLab (gitlab.com or self-hosted).

TODO: add feature for GitLab support

Below is the proposed architecture and plan generated by AI (opencode 1.17.8, Big Pickle model)

Proposed design

1. Define a RepoAdapter protocol/ABC that abstracts the methods used by
   the 9 eval functions (get_license, get_languages, get_contributors,
   get_contents, get_issues, has_wiki, etc.)
2. Implement a GitLabAdapter using the python-gitlab library
3. Detect the platform from the URL (github.com vs gitlab.com) and
   auto-select the adapter; support self-hosted GitLab instances via a
   config option
4. Add GITLAB_TOKEN env var alongside GITHUB_TOKEN
5. Update the agent instructions (project-evaluator.agent.md) with
   GitLab-specific API URLs for manual evaluation fallback
6. Update README and config.example.yaml

API mapping notes

Criterion	GitHub (PyGithub)	GitLab (python-gitlab)
Licensing	repo.get_license()	project.license (dict attr)
Technology	repo.get_languages()	project.languages()
Activity	repo.get_stats_commit_activity()	No direct weekly stats – query commits by date range
Contributors	repo.get_contributors()	project.repository_members.list()
Product Size	repo.get_languages() sum bytes	project.languages()
Issue Tracker	repo.get_issues()	project.issues.list()
New Contributor	repo.get_contents(path)	project.files.get(file_path=...)
Community	repo.get_contents(path)	project.files.get(file_path=...)
User Base	stars/forks/releases attrs	project.star_count / forks_count / releases.list()

Future extensibility

The RepoAdapter pattern also makes it straightforward to add other
platforms later (Bitbucket, SourceForge, Codeberg, Gitea, etc.) — each
just needs a new adapter class implementing the same protocol.