Fix background service, add support for NBT instead of Json

lib/pages/HomePage.dart

@@ -30,6 +30,18 @@ class _HomePageState extends State<HomePage> {
 
   void call() {
     setState(() {});
+
+    if (SessionData.DisplayError.isNotEmpty) {
+      ScaffoldMessenger.of(context).showSnackBar(
+        SnackBar(
+          content: Text(SessionData.DisplayError),
+          elevation: 8,
+          duration: Duration(seconds: 5),
+        ),
+      );
+
+      SessionData.DisplayError = "";
+    }
   }
 
   @override
@@ -393,3 +405,17 @@ class _HomePageState extends State<HomePage> {
     );
   }
 }
+
+class OverlayWidget extends StatefulWidget {
+  @override
+  State<StatefulWidget> createState() {
+    return _Overlay();
+  }
+}
+
+class _Overlay extends State<OverlayWidget> {
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold();
+  }
+}