Frontend first draft

frontend/pshared/lib/utils/share.dart

@@ -0,0 +1,7 @@
+import 'package:flutter/material.dart';
+
+
+Rect? sharePositionOrigin(BuildContext context) {
+  final RenderBox box = context.findRenderObject() as RenderBox;
+  return box.localToGlobal(Offset.zero) & box.size;
+}