优化更新代码，添加界面功能并整合

WPFluent/Appearance/SystemMenuThemeManager.cs

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+using Microsoft.Win32;
+
+using WPFluent.Interop;
+
+
+namespace WPFluent.Appearance;
+
+public static class SystemMenuThemeManager
+{
+    public static void Apply(SystemMenuTheme theme = SystemMenuTheme.Auto)
+    {
+        // Enable dark mode for context menus if using dark theme
+        if (Environment.OSVersion.Version.Build >= 18362) // Windows 10 1903
+        {
+            if (theme == SystemMenuTheme.Auto)
+            {
+                // UxTheme methods will apply all of menus.
+                // However, the Windows style system prefers that
+                // Windows System Menu is based on `Apps Theme`,
+                // and Tray Context Menu is based on `System Theme` when using a custom theme.
+                // But actually we can't have our cake and eat it too.
+                // Finally, we synchronize the theme styles of tray with higher usage rates.
+                if (ApplicationThemeManager.GetSystemTheme() == SystemTheme.Dark)
+                {
+                    _ = UxTheme.SetPreferredAppMode(UxTheme.PreferredAppMode.ForceDark);
+                    UxTheme.FlushMenuThemes();
+                }
+
+                // Synchronize the theme with system settings
+                SystemEvents.UserPreferenceChanged -= OnUserPreferenceChangedEventHandler;
+                SystemEvents.UserPreferenceChanged += OnUserPreferenceChangedEventHandler;
+            }
+            else if (theme == SystemMenuTheme.Dark)
+            {
+                SystemEvents.UserPreferenceChanged -= OnUserPreferenceChangedEventHandler;
+                _ = UxTheme.SetPreferredAppMode(UxTheme.PreferredAppMode.ForceDark);
+                UxTheme.FlushMenuThemes();
+            }
+            else if (theme == SystemMenuTheme.Light)
+            {
+                SystemEvents.UserPreferenceChanged -= OnUserPreferenceChangedEventHandler;
+                _ = UxTheme.SetPreferredAppMode(UxTheme.PreferredAppMode.ForceLight);
+                UxTheme.FlushMenuThemes();
+            }
+        }
+    }
+
+    private static void OnUserPreferenceChangedEventHandler(object sender, UserPreferenceChangedEventArgs e)
+    {
+        if (ApplicationThemeManager.GetSystemTheme() == SystemTheme.Dark)
+        {
+            _ = UxTheme.SetPreferredAppMode(UxTheme.PreferredAppMode.ForceDark);
+            UxTheme.FlushMenuThemes();
+        }
+        else
+        {
+            _ = UxTheme.SetPreferredAppMode(UxTheme.PreferredAppMode.ForceLight);
+            UxTheme.FlushMenuThemes();
+        }
+    }
+}
+
+/// <summary>
+/// Theme in which an system menu is displayed.
+/// </summary>
+public enum SystemMenuTheme
+{
+    /// <summary>
+    /// Auto system theme.
+    /// </summary>
+    Auto = ApplicationTheme.Unknown,
+
+    /// <summary>
+    /// Dark system theme.
+    /// </summary>
+    Dark = ApplicationTheme.Dark,
+
+    /// <summary>
+    /// Light system theme.
+    /// </summary>
+    Light = ApplicationTheme.Light,
+}