GH Teams Audit: Clean up repo access

I peeked into a few repos in the org and the permission scheme is a mess. There are arbitrary individual access. We should use GH Teams properly. Will take a while to clean up and I will inform the affected parties as needed (unless those that clearly aren't active anymore).

The issue mentions GitHub organization repositories, individual access, and Teams, but names no files, tests, or specific repositories. Start by inventorying current repository permissions and team membership, then identify the intended team-based mapping. Done means arbitrary individual access has been reviewed and cleaned up, with affected parties informed as needed.

Written by the indexing model from the issue text.