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/simulation/chunk_streaming.rs

@@ -66,7 +66,7 @@ pub fn chunk_streaming(
     };
 
     // Cadence gate — only run every N ticks
-    if cadence.ticks > 0 && time.tick % cadence.ticks != 0 {
+    if cadence.ticks > 0 && !time.tick.is_multiple_of(cadence.ticks) {
         return;
     }