fix: use derived override pattern for selectedQueue to avoid captured state warning

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

packages/frontend/src/routes/admin/queues/+page.svelte

@@ -17,7 +17,9 @@
 
   const queues = $derived(data.queues);
 
-  let selectedQueue = $state<string | null>(queues[0]?.name ?? null);
+  // null means "user hasn't picked yet" — fall back to first queue
+  let selectedQueueOverride = $state<string | null>(null);
+  const selectedQueue = $derived(selectedQueueOverride ?? queues[0]?.name ?? null);
   let selectedStatus = $state<string | null>(null);
   let jobs = $state<Job[]>([]);
   let loadingJobs = $state(false);
@@ -43,7 +45,7 @@
   }
 
   async function selectQueue(name: string) {
-    selectedQueue = name;
+    selectedQueueOverride = name;
     selectedStatus = null;
     await loadJobs();
   }