Add live room preview thumbnails

frontend/lib/pages/settings_page.dart

@@ -11,7 +11,7 @@ class SettingsPage extends StatefulWidget {
   const SettingsPage({super.key});
 
   @override
-  _SettingsPageState createState() => _SettingsPageState();
+  State<SettingsPage> createState() => _SettingsPageState();
 }
 
 class _SettingsPageState extends State<SettingsPage> {
@@ -221,6 +221,18 @@ class _SettingsPageState extends State<SettingsPage> {
                 );
               }).toList(),
             ),
+            const SizedBox(height: 32),
+            _buildSectionTitle("Explore"),
+            const SizedBox(height: 8),
+            SwitchListTile.adaptive(
+              contentPadding: EdgeInsets.zero,
+              title: const Text("Live Preview Thumbnails"),
+              subtitle: const Text(
+                "Show cached snapshot covers for live rooms when available.",
+              ),
+              value: settings.livePreviewThumbnailsEnabled,
+              onChanged: settings.setLivePreviewThumbnailsEnabled,
+            ),
             if (isAuthenticated) ...[
               const SizedBox(height: 32),
               _buildSectionTitle("Security"),