chore(simulation): address review suggestions — comments and minor fixes

- monologue.rs: tracing::warn on unrecognized trigger in fallback arm
- disclosure.rs: borrow-sequencing comment, first() simplification note
- trait_modifiers.rs: delegate parse_confidence to KnowledgeConfidence::try_from
- npc_knowledge_transfer.rs: fix misleading "draw randomly" comment,
  document one-directional transfer behavior
- graph.rs: document intentional no-retrigger after contradiction
- dialogue.rs: explain entity grant guardrail asymmetry (D-079)
- knowledge/mod.rs: document one-tick monologue lag from system ordering
- poi_discovery.rs: document D-079 carve-out for direct KG write

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

server/src/simulation/dialogue.rs

@@ -674,6 +674,11 @@ fn emit_knowledge_grant(
                 },
             });
         }
+        // Entity grants have no "NPC knows this entity" guardrail (unlike Fact
+        // grants above). This is intentional per D-079: entity grants introduce
+        // NEW knowledge about an entity the NPC is talking about — the NPC
+        // doesn't need to "know" the entity in their own KG to reference it
+        // in dialogue. The entity_ref resolves via ContentEntityRegistry, not KG.
         KnowledgeGrant::Entity {
             entity_ref,
             attributes,