优化更新代码，添加界面功能并整合

WPFluent/Controls/NavigationView/NavigationViewItemSeparator.cs

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+
+
+
+// Based on Windows UI Library
+// Copyright(c) Microsoft Corporation.All rights reserved.
+
+// ReSharper disable once CheckNamespace
+namespace WPFluent.Controls;
+
+// https://docs.microsoft.com/en-us/uwp/api/windows.ui.xaml.controls.navigationviewitemseparator?view=winrt-22621
+
+/// <summary>
+/// Represents a line that separates menu items in a NavigationMenu.
+/// </summary>
+public class NavigationViewItemSeparator : System.Windows.Controls.Separator
+{
+}