Run the PR test workflow through npm run test:coverage and generate a
repo-hosted coverage badge payload from coverage summary output.
Use c8 directly from npm scripts and emit text, lcov, and json-summary
reports so CI can update badge data without external coverage services.
Replace the README coverage badge source with a shields endpoint that
reads badges/coverage.json, auto-commit badge updates on master pushes,
handle non-fast-forward push races with fetch/rebase retries, and scope
write token permission to a push-only badge update job.
Co-authored-by: kiloconnect[bot] <240665456+kiloconnect[bot]@users.noreply.github.com>
