Maintenance/CI-hygiene patch release: GitHub Actions upgraded off the
deprecated Node 20 runtime, plus a one-patch @types/node bump. See
CHANGELOG.md for full detail.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01FSESg485K55fz5e6NdmCNe