~x-ai/grok-latest → A (3:1)

A is a precise production bugfix that defines the missing GITHUB_API_BASE_URL (with default and rstrip) so the GitHub OAuth callback no longer raises NameError. B is a pure test-suite refactor that extracts duplicated helpers (assert/ANSI, HTTP clients, mock Google, cargo build, server env, registration) into common.bb/oauth.bb without changing product behavior or fixing runtime issues.