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/voice/worker.rs

@@ -165,9 +165,13 @@ impl VoicePipe {
             .spawn()
             .map_err(|e| format!("failed to spawn sr-voice: {}", e))?;
 
-        let stdin = child.stdin.take()
+        let stdin = child
+            .stdin
+            .take()
             .ok_or_else(|| "failed to capture sr-voice stdin".to_string())?;
-        let stdout = child.stdout.take()
+        let stdout = child
+            .stdout
+            .take()
             .ok_or_else(|| "failed to capture sr-voice stdout".to_string())?;
 
         Ok(Self {