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/knowledge/graph.rs

@@ -177,6 +177,12 @@ impl KnowledgeGraph {
         }
         // Contradicted entries without a new contradiction stay Contradicted —
         // the previous contradiction is still unresolved.
+        //
+        // After this write, entry.source is DirectObservation, so subsequent
+        // observations will NOT re-trigger contradiction detection (the
+        // pre-overwrite check only fires when existing.source is ToldBy).
+        // This is intentional: once contradicted, the entry reflects the
+        // observer's own eyes and cannot be "contradicted" again by looking.
 
         contradiction
     }

server/src/knowledge/mod.rs

@@ -37,6 +37,10 @@ impl Plugin for KnowledgePlugin {
             .add_systems(
                 Update,
                 (
+                    // Runs after snapshot: contradiction monologue and relationship
+                    // shifts from KnowledgeGranted events lag by one tick (~0.1s).
+                    // Acceptable — the player perceives the contradiction on the
+                    // next snapshot, which reads as a natural reaction delay.
                     events::process_knowledge_events
                         .after(crate::perception::observer::compute_observer_snapshot),
                     events::decay_knowledge.after(events::process_knowledge_events),