fix(simulation): address PR #56 review — pipeline extraction, ActiveDialogue, range check

Tyre #1: Extract run_dialogue_pipeline() shared helper — eliminates ~60
lines of duplication between process_talk_interaction and
process_dialogue_response (L1-L4 pipeline).

Hoshe #1: process_dialogue_response now updates ActiveDialogue with
current tick on follow-up selection — prevents stale started_tick.

Tyre #4: process_dialogue_response now updates InteractionMemory on
follow-up — multi-turn conversations are visible in history.

Hoshe #6 / Tyre #6: handle_dialogue_response adds server-side range
check (CLOSE_RANGE), matching Talk/Confront pattern (D-010 info
boundary).

Hoshe #2: Weighted selection fallback replaced with unreachable!() —
score_line always returns >= 1, so the fallback was dead code.

Hoshe #3: assert!(false, ...) → panic!() in serialization.rs (clippy).

Hoshe #4: SetFacing and TeleportToHub added to roundtrip test.

Hoshe #5: setup_dialogue_response_world inlined (trivial pass-through).

Tyre #2: Doc comment on DialogueCooldownTracker explains per-player-global
design choice (line IDs are NPC-scoped per D-035, no collision risk).

Tyre #3: CONFRONTATION_LINES comment updated with TODO for D-028/D-035
migration.

Tyre #5: DialogueResponse fixture added for cross-language GDScript
testing (input_dialogue_response.msgpack).

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

server/tests/gen_fixtures.rs

@@ -253,6 +253,19 @@ fn generate_msgpack_fixtures() {
         &rmp_serde::to_vec_named(&input_batch).unwrap(),
     );
 
+    // PlayerInput: DialogueResponse (#539)
+    let input_dialogue_response = PlayerInput {
+        tick: 300,
+        action: PlayerAction::DialogueResponse {
+            target_entity_id: 42,
+            response_id: "kael-davan_d_001".to_string(),
+        },
+    };
+    write_fixture(
+        "input_dialogue_response",
+        &rmp_serde::to_vec_named(&input_dialogue_response).unwrap(),
+    );
+
     // Diagonal movement fixtures (clockwise: NE, SE, SW, NW)
     for (name, action) in [
         ("input_move_northeast", PlayerAction::MoveNortheast),

server/tests/serialization.rs

@@ -107,6 +107,10 @@ fn all_player_action_variants_roundtrip() {
         PlayerAction::ToggleStanceUp,
         PlayerAction::ToggleStanceDown,
         PlayerAction::WalkAway,
+        PlayerAction::SetFacing {
+            facing: "north".to_string(),
+        },
+        PlayerAction::TeleportToHub,
         PlayerAction::DialogueResponse {
             target_entity_id: 42,
             response_id: "kael-davan_d_001".to_string(),
@@ -173,8 +177,7 @@ fn all_fixtures_deserialize() {
             rmp_serde::from_slice::<u64>(&bytes)
                 .unwrap_or_else(|e| panic!("deserialize boundary raw fixture {}: {}", name, e));
         } else {
-            assert!(
-                false,
+            panic!(
                 "unknown fixture naming convention: {} — add a deserialization branch for this prefix",
                 name
             );