Fix Import issue (#61)

* Remove conditional import

* fix pickWeb

* Fix all issues

* fix import issue

Co-authored-by: Xin Yao <singerdmx@gmail.com>

lib/widgets/editor.dart

@@ -110,6 +110,7 @@ Widget _defaultEmbedBuilder(BuildContext context, leaf.Embed node) {
 }
 
 Widget _defaultEmbedBuilderWeb(BuildContext context, leaf.Embed node) {
+  var ui = UniversalUI();
   switch (node.value.type) {
     case 'image':
       String imageUrl = node.value.data;