performance-ci

Measure where a repository's GitHub Actions time goes and how to cut it. Pulls the last 150 completed runs with gh and splits every job into waiting for a machine, setup (checkout, installs, cache restore) and the job's own work. Lists the slowest jobs, then checks nine causes: runner queueing, slow lint, slow typechecking, unsharded tests or small machines, test files that reload the app, slow setup, jobs that don't run in parallel, full test runs on every PR, and no local checks before push. Each fix gets its file and line and the seconds it saves. Changes that cost money or run fewer tests go in a separate list for you to decide. Read-only until you pick the fixes.