feat(simulation): sprint 16 dialogue server — response handler, trust gossip, variety tracker

Move dialogue system registrations from BridgePlugin to NpcPlugin (#538):
game logic that depends on NPC-layer resources now registers where it
belongs. BridgePlugin retains only wire protocol concerns.

Implement DialogueResponse verb handler (#539): new process_dialogue_response
system runs the full D-028 four-layer pipeline to select follow-up lines
when the player picks a dialogue option. Clears ActiveDialogue when no
candidates remain. Fix latent schedule ambiguity — emit_observation_events
now has explicit .before(advance_tick) constraint.

Verify trust-gated gossip pipeline (#171): confirmed process_talk_interaction
correctly passes KnowledgeConfidence through relationship_to_trust() per
D-075. Added integration tests for Secret-tier access (Friendly+KnowsDetails)
and Surface-only fallback (Friendly+Suspects).

Wire DialogueCooldownTracker into selection (#338): added regression test
confirming no line_id repeats within the 600-tick cooldown window across
10 consecutive Talk interactions.

Closes #538, #539, #171, #338

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

server/src/simulation/input.rs

@@ -280,6 +280,18 @@ pub fn process_player_input(
             PlayerAction::TeleportToHub => {
                 handle_teleport_to_hub(&mut player_query, &mut commands);
             }
+            PlayerAction::DialogueResponse {
+                target_entity_id,
+                ref response_id,
+            } => {
+                handle_dialogue_response(
+                    &mut commands,
+                    &registry,
+                    &player_query,
+                    target_entity_id,
+                    response_id,
+                );
+            }
             PlayerAction::UsePerceptionMode(ref mode) => {
                 tracing::trace!("UsePerceptionMode({}) — no-op for Sprint 1", mode);
             }
@@ -458,6 +470,44 @@ fn handle_talk(
     tracing::debug!(target_id, "Talk: TalkRequest marker set on player");
 }
 
+/// Handle DialogueResponse action: set DialogueResponseRequest marker (#539).
+/// The follow-up dialogue pipeline runs in process_dialogue_response (dialogue.rs).
+#[allow(clippy::type_complexity)]
+fn handle_dialogue_response(
+    commands: &mut Commands,
+    registry: &EntityRegistry,
+    player_query: &Query<
+        (
+            Entity,
+            &TilePosition,
+            Option<&mut Stance>,
+            Option<&mut PlayerMoveCooldown>,
+        ),
+        With<PlayerCharacter>,
+    >,
+    target_entity_id: u64,
+    response_id: &str,
+) {
+    let Ok((player_entity, _, _, _)) = player_query.single() else {
+        return;
+    };
+
+    let target_stable = StableId(target_entity_id);
+    let Some(target_entity) = registry.to_entity(&target_stable) else {
+        tracing::warn!(target_entity_id, "DialogueResponse: target entity not in registry");
+        return;
+    };
+
+    commands
+        .entity(player_entity)
+        .insert(crate::simulation::dialogue::DialogueResponseRequest {
+            target: target_entity,
+            response_id: response_id.to_string(),
+        });
+
+    tracing::debug!(target_entity_id, response_id, "DialogueResponse: marker set on player");
+}
+
 /// Handle Confront verb: set ConfrontationDelivered marker on the player entity (#520, D-063).
 /// The confrontation response system runs in process_confrontation_response (dialogue.rs).
 /// Server-side range check: Confront requires CLOSE_RANGE (same as Talk).
@@ -741,7 +791,8 @@ fn handle_teleport_to_hub(
             .remove::<crate::simulation::dialogue::TalkRequest>()
             .remove::<crate::simulation::dialogue::ActiveDialogue>()
             .remove::<crate::simulation::dialogue::WalkAwayRequest>()
-            .remove::<crate::simulation::dialogue::ConfrontationDelivered>();
+            .remove::<crate::simulation::dialogue::ConfrontationDelivered>()
+            .remove::<crate::simulation::dialogue::DialogueResponseRequest>();
 
         tracing::info!(
             x = hub_spawn.x,