Add mlinter inline PR review posting
- setup.py: pin mlinter to collect_violations branch (--output-json with rule specs)
- utils/post_mlinter_review.py: post findings as inline PR review comments
- pr-ci-post-dashboard-link.yml: add post-mlinter-review job
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
