feat: implement issue #2243 — [qa-lead reach] Retire qa-lead-pr-advisory.yml — the persona-mention router now serves the pull_request advisory alone
Problem
[qa-lead reach] Retire qa-lead-pr-advisory.yml — the persona-mention router now serves the pull_request advisory alone
From the issue: Retire .github/workflows/qa-lead-pr-advisory.yml: qa-lead's pull_request advisory is now served by the shared persona-mention router, and the two paths only coexist today because both run the same already-advised check on the <!-- persona:qa-lead --> marker, so a PR gets one advisory. This is the last story of epic #1643 (ADR-0009, decision (b)).
Risk
Medium — changes GitHub Actions workflow behavior, which is exercised only post-merge; verify via the affected workflow runs.
Test plan
Tests added/updated: tests/test_persona_pr_pregate.bats. Verification: bash scripts/dev-lead-lint.sh (shellcheck --severity=warning) ran pre-commit; the bats suite runs in CI.
Rollback
Revert this PR. No non-revertible side effects (no tags, migrations, or external state).
Monitoring
Watch the affected workflow run(s) in the Actions tab and this PR's Lint check for regressions.
Closes #2243