Fix queue list crash: empty-state element destroyed by innerHTML

loadQueue() used getElementById('empty-state') on each call, but the
first successful render wiped it with innerHTML=''. Every subsequent
call got null and threw TypeError on .style access, silently killing
all future list refreshes. Counters kept working because updateStats()
runs independently.

Fix: recreate the empty state as innerHTML string instead of
referencing a DOM element that gets destroyed.

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

app/templates/queue.html

@@ -401,7 +401,6 @@ Storage.init().then(() => {
 
 async function loadQueue() {
     const queueList = document.getElementById('queue-list');
-    const emptyState = document.getElementById('empty-state');
 
     const photos = await Storage.db.photos
         .where('username').equals(currentUsername)
@@ -413,21 +412,18 @@ async function loadQueue() {
     const completedPhotos = photos.filter(p =>
         p.status === 'verified' || p.status === 'failed');
 
-    if (photos.length === 0) {
-        emptyState.style.display = 'block';
-        queueList.innerHTML = '';
-        queueList.appendChild(emptyState);
-        document.getElementById('sync-now-btn').disabled = true;
-        return;
-    }
-
-    emptyState.style.display = 'none';
     // Revoke old ObjectURLs before rebuilding to prevent memory leaks
     queueList.querySelectorAll('img[src^="blob:"]').forEach(img => {
         URL.revokeObjectURL(img.src);
     });
     queueList.innerHTML = '';
 
+    if (photos.length === 0) {
+        queueList.innerHTML = '<p class="empty-state">No photos in queue</p>';
+        document.getElementById('sync-now-btn').disabled = true;
+        return;
+    }
+
     // Show active uploads first (newest first)
     for (const photo of activePhotos.reverse()) {
         queueList.appendChild(createQueueItem(photo, false));