ci: add hotspot code health gate via CodeScene API (≥8.50 floor)

.github/workflows/ci.yml

@@ -57,11 +57,32 @@ jobs:
             --fail-under-lines 85
         # cargo-llvm-cov exits non-zero if line coverage drops below 85%
 
-      # ── 3. Code Health (CodeScene) ───────────────────────────────────────
-      # CodeScene PR reviews are handled via webhook integration configured
-      # in the CodeScene dashboard — not via a GitHub Action.
-      # No CI step needed here; CodeScene posts review comments directly on PRs
-      # and can block merges via its own GitHub App status check.
+      # ── 3. Code Health (CodeScene — Hotspot Code Health gate) ────────────
+      # The webhook integration handles per-PR delta analysis (posts review
+      # comments on PRs). This step enforces a minimum floor on the
+      # project-wide Hotspot Code Health score (weighted avg of the most
+      # frequently edited files — the ones that matter most).
+      # Current baseline: 8.73 | Aspirational target: 9.5
+      - name: Hotspot Code Health gate (≥8.50)
+        env:
+          CODESCENE_PAT: ${{ secrets.CODESCENE_PAT }}
+          CODESCENE_PROJECT_ID: ${{ secrets.CODESCENE_PROJECT_ID }}
+        run: |
+          THRESHOLD=8.50
+          SCORE=$(curl -sf \
+            -H "Authorization: Bearer $CODESCENE_PAT" \
+            -H "Accept: application/json" \
+            "https://api.codescene.io/v2/projects/$CODESCENE_PROJECT_ID" \
+            | python3 -c "import sys,json; d=json.load(sys.stdin); print(d['analysis']['hotspot_code_health']['now'])")
+          echo "Hotspot Code Health: $SCORE (threshold: $THRESHOLD)"
+          python3 -c "
+          score = float('$SCORE')
+          threshold = float('$THRESHOLD')
+          if score < threshold:
+              print(f'❌ Hotspot Code Health {score:.2f} is below threshold {threshold}')
+              exit(1)
+          print(f'✅ Hotspot Code Health {score:.2f} ≥ {threshold}')
+          "
 
       # ── 4. Documentation check (warning only — does not fail build) ───────
       - name: Check docs are updated