Investigate better GitHub mocking for tests

[oldsj]

Problem

Need better approaches for mocking GitHub in tests.

Areas to Investigate

• GitHub API mocking libraries/tools
• Local GitHub server alternatives (e.g., mock servers, gitea)
• Fixture-based approaches for common GitHub responses
• Integration test strategies that minimize real API calls
• Rate limit handling in test environments

Goals

• Faster, more reliable tests
• No dependency on real GitHub API during test runs
• Realistic mock responses that match actual GitHub behavior
• Easy to maintain and update mocks

Questions to Answer

• What are other projects using for GitHub mocking?
• Should we use a local git server vs API mocking?
• How do we handle webhook testing?
• What's the right balance between mocked vs real integration tests?