improve:光标显示

Ink Canvas/MainWindow_cs/MW_ShapeDrawing.cs

@@ -103,6 +103,9 @@ namespace Ink_Canvas {
         }
 
         private void BtnPen_Click(object sender, RoutedEventArgs e) {
+            // 禁用高级橡皮擦系统
+            DisableAdvancedEraserSystem();
+            
             // 如果当前已是批注模式，再次点击弹出批注子面板
             if (penType == 0 && inkCanvas.EditingMode == InkCanvasEditingMode.Ink && !drawingAttributes.IsHighlighter) {
                 return;