chore(lint): burn down remaining warnings to zero

src/gateway/handlers/system.ts

@@ -59,7 +59,8 @@ export function createSystemHandlers(deps: SystemHandlerDeps) {
     },
 
     'system.restart': async (request: GatewayRequest): Promise<OutboundMessage> => {
-      if (!deps.restart) {
+      const restart = deps.restart;
+      if (!restart) {
         return makeError(request.id, ErrorCode.InternalError, 'Restart not available in this environment');
       }
 
@@ -68,7 +69,7 @@ export function createSystemHandlers(deps: SystemHandlerDeps) {
 
       // Schedule restart after response is sent (next tick)
       queueMicrotask(() => {
-        deps.restart!().catch((err) => {
+        restart().catch((err) => {
           console.error('Restart failed:', err);
         });
       });