github-actions-prevent-waste

# Prevent wasted GitHub Actions runs For PR checks, cancel superseded runs and skip jobs while the PR is a draft: ```yaml on: pull_request: types: [opened, synchronize, reopened, ready_for_review, converted_to_draft] concurrency: group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.ref }} cancel-in-progress: true ``` - Keep keys stable across commits: use a unique workflow prefix and PR number or ref, never a commit SHA or run ID. Reusable workflows inherit the caller's `github.workflow`; keep caller and callee concurrency keys distinct. - Add `github.event.pull_request.draft != true` to each check job's existing `if`, including reusable-workflow callers and aggregate jobs. Job guards prevent runner allocation; step guards still allocate runners. - Preserve existing triggers when adding `ready_for_review` and `converted_to_draft`. The former starts checks when review begins; the latter lets a replacement run cancel old work before its jobs skip. - Concurrency cancellation needs a new run in the same group. If path filters prevent that run, use a trusted cleanup workflow on PR updates to cancel only older heads, rechecking the current head before cancellation. Never check out PR code in privileged cleanup. References: [concurrency](https://docs.github.com/en/actions/how-tos/write-workflows/choose-when-workflows-run/control-workflow-concurrency), [PR events](https://docs.github.com/en/actions/reference/workflows-and-actions/events-that-trigger-workflows#pull_request).