Release v1.7.2

What changed

• Added non-blocking mutation testing baseline using Cosmic Ray.
• Added mutation CI artifact publication (mutation-summary.md, cosmic-ray-results.ndjson, cr-
  session.sqlite).
• Added targeted validator guardrail tests to eliminate mutation survivors on boundary/additive
  contract paths.
• Updated mutation workflow upload action to actions/upload-artifact@v5.
• Enabled Node24 JS action runtime in mutation workflow (FORCE_JAVASCRIPT_ACTIONS_TO_NODE24=true).

Why it matters

• Improves confidence in test quality beyond line coverage.
• Makes mutation diagnostics auditable directly from CI artifacts.
• Reduces CI platform-risk ahead of Node20 deprecation in GitHub Actions.

Notes

• v1.7.2 is an engineering hardening patch release.
• No CLI or runtime behavior changes.
• No output schema/contract changes.

GitHub Pull Requests Included

• ci(v1.7.2): add non-blocking mutation testing baseline with cosmic-ray by @damienSavoldelli in #41
• ci: upgrade mutation artifact upload action to v5 by @damienSavoldelli in #42
• release: prepare v1.7.2 by @damienSavoldelli in #43

Full Changelog: v1.7.1...v1.7.2