Install RoboTruth in CI

name: RoboTruth Audit

on:
  pull_request:
    types: [opened, synchronize]

jobs:
  robotruth:
    runs-on: ubuntu-latest
    steps:
      - name: Audit PR with RoboTruth
        run: |
          pip install httpx --quiet
          python - <<'EOF'
          import httpx, os, sys
          url = os.environ["PR_URL"]
          r = httpx.post(
            "https://robotruth.vercel.app/api/audit",
            json={"url": url},
            timeout=60,
          )
          d = r.json()["receipt"]
          print(f"RoboTruth: {d['verdict']} · Grade {d['grade']}")
          print(f"  {d['math']}")
          if d["undisclosed"]:
            for f in d["undisclosed"]:
              print(f"  ⚠ {f['label']} — {f.get('file','')}:{f.get('line','')}")
          sys.exit(0 if d["grade"] in ("A", "B") else 1)
          EOF
        env:
          PR_URL: ${{ github.event.pull_request.html_url }}