优化更新代码，添加界面功能并整合

WPFluent/Controls/NavigationView/INavigationViewItem.cs

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+
+
+
+/* Based on Windows UI Library
+   Copyright(c) Microsoft Corporation.All rights reserved. */
+
+
+using System.Collections;
+using System.Windows.Controls;
+
+// ReSharper disable once CheckNamespace
+namespace WPFluent.Controls;
+
+/// <summary>
+/// Represents the container for an item in a NavigationView control.
+/// </summary>
+public interface INavigationViewItem
+{
+    /// <summary>
+    /// Add / Remove ClickEvent handler.
+    /// </summary>
+    [Category("Behavior")]
+    event RoutedEventHandler Click;
+
+    internal bool IsMenuElement { get; set; }
+
+    /// <summary>
+    /// Correctly activates
+    /// </summary>
+    void Activate(INavigationView navigationView);
+
+    /// <summary>
+    /// Correctly deactivates
+    /// </summary>
+    void Deactivate(INavigationView navigationView);
+
+    /// <summary>
+    /// Gets or sets the content
+    /// </summary>
+    object Content { get; set; }
+
+    /// <summary>
+    /// Gets or sets the icon displayed in the MenuItem object.
+    /// </summary>
+    IconElement? Icon { get; set; }
+
+    /// <summary>
+    /// Gets the unique identifier that allows the item to be located in the navigation.
+    /// </summary>
+    string Id { get; }
+
+    InfoBadge? InfoBadge { get; set; }
+
+    /// <summary>
+    /// Gets a value indicating whether the current element is active.
+    /// </summary>
+    bool IsActive { get; }
+
+    /// <summary>
+    /// Gets or sets a value indicating whether the sub-<see cref="MenuItems"/> are expanded.
+    /// </summary>
+    bool IsExpanded { get; internal set; }
+
+    /// <summary>
+    /// Gets the collection of menu items displayed in the NavigationView.
+    /// </summary>
+    IList MenuItems { get; }
+
+    /// <summary>
+    /// Gets or sets an object source used to generate the content of the NavigationView menu.
+    /// </summary>
+    object? MenuItemsSource { get; set; }
+
+    /// <summary>
+    /// Gets or sets the caching characteristics for a page involved in a navigation.
+    /// </summary>
+    NavigationCacheMode NavigationCacheMode { get; set; }
+
+    /// <summary>
+    /// Gets or sets the parent if it's in <see cref="MenuItems"/> collection
+    /// </summary>
+    INavigationViewItem? NavigationViewItemParent { get; internal set; }
+
+    /// <summary>
+    /// Gets or sets the unique tag used by the parent navigation system for the purpose of searching and navigating.
+    /// </summary>
+    string TargetPageTag { get; set; }
+
+    /// <summary>
+    /// Gets or sets the type of the page to be navigated. (Should be derived from <see cref="FrameworkElement"/>).
+    /// </summary>
+    Type? TargetPageType { get; set; }
+
+    /// <summary>
+    /// Gets or sets the template property
+    /// </summary>
+    ControlTemplate? Template { get; set; }
+}