feat(F-139): completed feature

work/artifacts/F-139/qa.json

@@ -0,0 +1,12 @@
+{
+  "feature_id": "F-139",
+  "agent": "qa",
+  "stage": "qa_gate",
+  "verdict": "APPROVED",
+  "summary": "tsc 0, verify.sh green. No regressions.",
+  "checks": [
+    {"item": "tsc 0", "ok": true, "evidence": "npm run build 0 errors"},
+    {"item": "verify.sh", "ok": true, "evidence": "exit 0"}
+  ],
+  "issues": []
+}