fix: delete stale sticky comment when local tests pass on re-run

[Soul-Craft]

Summary

• When ci-verify-local transitions from failure → success on a re-run, the "## Local tests" sticky comment posted by the failure run was never cleaned up — it stayed on the PR indefinitely.
• Added a new Clean up stale sticky comment on success step that runs only on the success path, queries for any existing comment starting with "## Local tests", and deletes it via DELETE /repos/{owner}/{repo}/issues/comments/{id}.
• No permission changes needed — pull-requests: write was already declared for the failure path's POST/PATCH.

What changed

.github/workflows/ci-verify-local.yml — added a step between "Pass if evidence found" and "Post sticky comment if missing or failed":

- name: Clean up stale sticky comment on success
  if: steps.check.outputs.status == 'success'
  env:
    GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
    PR_NUMBER: ${{ github.event.pull_request.number }}
    REPO: ${{ github.repository }}
  run: |
    set -euo pipefail
    existing=$(gh api "repos/$REPO/issues/$PR_NUMBER/comments" --paginate \
      --jq '.[] | select(.body | startswith("## Local tests")) | .id' | head -1)
    if [ -n "$existing" ]; then
      gh api "repos/$REPO/issues/comments/$existing" --method DELETE
      echo "Deleted stale sticky comment $existing"
    fi

The startsWith("## Local tests") predicate matches both the "not yet uploaded" and "failed" comment variants — the same predicate used by the failure path's update logic.

Reviewer notes

• head -1 guards against the edge case where two matching comments exist (e.g. from concurrent runs).
• All ${{ }} interpolations go through env: variables — consistent with the existing security posture documented at the top of the file.
• The step is a no-op when no sticky comment exists (silent if [ -n "$existing" ] guard).

Test plan

• Open a PR, trigger a failure run (missing or failed local tests) — confirm sticky comment is posted
• Upload passing results, push a new commit — confirm next workflow run deletes the comment
• Confirm no comment is posted/touched when success runs with no prior sticky comment

🤖 Generated with Claude Code