fix(simulation): Clippy cleanup and CI enforcement (#635)

Fix all Clippy warnings across the server codebase (2411 insertions, 1341
deletions). Raise type-complexity-threshold to 750 and too-many-arguments
to 12 in .clippy.toml for idiomatic Bevy ECS system signatures. The server
now passes `cargo clippy -- --deny warnings` cleanly.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

server/src/npc/mood.rs

@@ -18,10 +18,10 @@
 use bevy_ecs::prelude::*;
 use serde::{Deserialize, Serialize};
 
-use crate::simulation::line_pool::Mood as ContentMood;
 use crate::npc::interaction::InteractionMemory;
 use crate::npc::{Npc, ToleranceThreshold};
 use crate::simulation::dialogue::CurrentMood;
+use crate::simulation::line_pool::Mood as ContentMood;
 use crate::simulation::tier::ActiveSim;
 use crate::simulation::time::{DayPhase, SimulationTime};
 
@@ -293,10 +293,7 @@ mod tests {
 
     #[test]
     fn mood_warm_when_positive_interaction() {
-        assert_eq!(
-            derive_mood(0, 50, DayPhase::Morning, true),
-            NpcMood::Warm
-        );
+        assert_eq!(derive_mood(0, 50, DayPhase::Morning, true), NpcMood::Warm);
     }
 
     #[test]
@@ -381,10 +378,7 @@ mod tests {
     #[test]
     fn mood_priority_warm_over_frustrated() {
         // Warm takes priority over Frustrated (checked before Evening test)
-        assert_eq!(
-            derive_mood(25, 50, DayPhase::Evening, true),
-            NpcMood::Warm
-        );
+        assert_eq!(derive_mood(25, 50, DayPhase::Evening, true), NpcMood::Warm);
     }
 
     #[test]
@@ -489,12 +483,7 @@ mod tests {
 
         // No ToleranceThreshold → defaults (stress=0, threshold=50) → Content
         let npc = world
-            .spawn((
-                Npc,
-                ActiveSim,
-                MoodState::default(),
-                CurrentMood::default(),
-            ))
+            .spawn((Npc, ActiveSim, MoodState::default(), CurrentMood::default()))
             .id();
 
         let mut schedule = bevy_ecs::schedule::Schedule::default();
@@ -669,7 +658,12 @@ mod tests {
         // This test documents the invariant: derive_mood never emits these states.
         use std::collections::HashSet;
 
-        let phases = [DayPhase::Morning, DayPhase::Afternoon, DayPhase::Evening, DayPhase::Night];
+        let phases = [
+            DayPhase::Morning,
+            DayPhase::Afternoon,
+            DayPhase::Evening,
+            DayPhase::Night,
+        ];
         let stresses: &[i16] = &[-50, -1, 0, 1, 19, 20, 29, 30, 49, 50, 51, 100];
         let thresholds: &[i16] = &[0, 1, 50, 100];
         let warm_flags = [false, true];