feat: online verification, node removals, and knowledge browser

Adds claim-bound online evidence records and citation verification scripts,
node removal transport/adapter, retrieval benchmark and owner-review tooling,
GraphCanvas/SourceDetail knowledge browser UI, and the ingest handoff helper.
Bumps the agents/gewu pack to the online-verification branch.

scripts/governing_answer_map.json

@@ -0,0 +1,10 @@
+{
+  "schema_version": 1,
+  "answers": {
+    "Q37": ["evidence.bibliography_is_not_primary_evidence"],
+    "Q39": [
+      "evidence.source_content_is_untrusted",
+      "scope.project_intent_is_resolved_from_service"
+    ]
+  }
+}