fix: normalize completed Nemotron reviews

Codex-authored final evidence-priority guard.

app.py

@@ -51,6 +51,9 @@ def run_audit(front_text: str, back_text: str):
     }
     try:
         result.agent_review = nemotron_review(snapshot)
+        if result.agent_review.status == "COMPLETE" and not result.investigation.missing_evidence:
+            result.agent_review.priority = "No additional claim-resolving evidence is required."
+            result.agent_review.evidence_request = ""
     except Exception as exc:
         result.agent_review = {
             "status": "UNAVAILABLE",