优化更新代码，添加界面功能并整合

WPFluent/Controls/TreeModelListView/TreeModelObject{T}.cs

@@ -0,0 +1,8 @@
+using System.Collections.ObjectModel;
+
+namespace WPFluent.Controls;
+
+public class TreeModelObject<T> where T : new()
+{
+    public virtual ObservableCollection<T> Children { get; set; } = [];
+}