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/mod.rs

@@ -126,7 +126,6 @@ pub struct NpcVoiceProfile {
     pub culture_id: String,
 }
 
-
 /// NPC animation tier (D-047).
 ///
 /// Tier 1 (clear): public daily activities — instantly readable.