folder restructuring

lib/widget/unimplemented_dialog.dart

@@ -0,0 +1,7 @@
+import 'package:flutter/material.dart';
+
+class UnimplementedDialog {
+  static void show(BuildContext context) {
+    showDialog(context: context, builder: (context) => const AlertDialog(content: Text('Not implemented yet')));
+  }
+}