fix(agents): reviewers drop a finding only with a Declined to Judge line, research-scout gets Tavily, no dead override reference

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

agents/review-coordinator.md

@@ -65,7 +65,8 @@ You will receive a prompt containing:
   (reasonableness filter) except the brief-conflict rule, which applies in every mode;
   Passes 1, 2, 4 still run.
 - **Rule catalogue** — `lib/review/rule-catalogue.mjs`. Findings whose
-  `rule_key` is not in this set are dropped by Pass 3.
+  `rule_key` is not in this set are routed to `unverified` by Pass 3
+  (`unknown-rule_key`).
 
 ## Your 4-pass process