improve:截图及浮动栏及代码优化

Ink Canvas/Windows/HistoryRollbackWindow.xaml.cs

@@ -1,4 +1,3 @@
-using Ink_Canvas.Helpers;
 using System;
 using System.Collections.Generic;
 using System.ComponentModel;
@@ -8,6 +7,8 @@ using System.Threading.Tasks;
 using System.Windows;
 using System.Windows.Controls;
 using System.Windows.Input;
+using Ink_Canvas.Helpers;
+
 // Added for OrderByDescending
 
 namespace Ink_Canvas