test: add deterministic rank-smoke for /api/rank-feedback

Add scripts/rank-smoke.mjs to verify:
- Core response shape and handoff contract
- Deterministic scoring for same payload
- Build order lane sanity (do/validate/defer/park)
- Guardrail defense: recommendedLane=park respected, non-goal conflicts prevent do lane

Tightens Scattermind→Ranker bridge contract without deployment changes.

package.json

@@ -8,7 +8,8 @@
     "start": "node server.js",
     "check": "node --check server.js && node --check scripts/setup-appwrite.mjs && node --check scripts/check-rank-feedback.mjs && node --check public/app.js && node scripts/check-rank-feedback.mjs",
     "setup:appwrite": "node scripts/setup-appwrite.mjs",
-    "smoke": "node scripts/smoke.mjs"
+    "smoke": "node scripts/smoke.mjs",
+    "rank-smoke": "node scripts/rank-smoke.mjs"
   },
   "keywords": [],
   "author": "",