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/settings/mod.rs

@@ -192,13 +192,12 @@ pub struct SettingsPlugin;
 
 impl Plugin for SettingsPlugin {
     fn build(&self, app: &mut App) {
-        app.init_resource::<SettingsCommandBuffer>()
-            .add_systems(
-                Update,
-                process_settings_commands
-                    .after(crate::simulation::input::process_player_input)
-                    .before(crate::perception::observer::compute_observer_snapshot),
-            );
+        app.init_resource::<SettingsCommandBuffer>().add_systems(
+            Update,
+            process_settings_commands
+                .after(crate::simulation::input::process_player_input)
+                .before(crate::perception::observer::compute_observer_snapshot),
+        );
         tracing::debug!("SettingsPlugin initialized");
     }
 }