'npm test' (default vitest thread pool) fails in ~1s on this Gitea Actions
runner for no reason reproducible locally (plain run, CI=true, and a fully
fresh rm -rf node_modules && npm ci all pass 215/215). Forcing the forks
pool with a small fixed worker count (min 1, max 2) is a standard fix for
this class of CI-only vitest worker-pool crash.
db83d77162