Fix navbar notifications icon to only show when "has notifications" icon when undismissed ones

lib/controls/app_bottom_nav_bar.dart

@@ -23,7 +23,8 @@ class AppBottomNavBar extends StatelessWidget {
   @override
   Widget build(BuildContext context) {
     final notificationManager = context.watch<NotificationsManager>();
-    final hasNotifications = notificationManager.notifications.isNotEmpty;
+    final hasNotifications =
+        notificationManager.notifications.where((n) => !n.dismissed).isNotEmpty;
     return BottomNavigationBar(
       onTap: (index) {
         final newButton = _indexToButton(index);