优化更新代码，添加界面功能并整合

WPFluent/Designer/DesignerHelper.cs

@@ -0,0 +1,38 @@
+
+
+
+namespace WPFluent.Designer;
+
+/// <summary>
+/// Helper class for Visual Studio designer.
+/// </summary>
+public static class DesignerHelper
+{
+    private static bool _isInDesignMode = default;
+    private static bool _isValueAlreadyValidated = default;
+
+    private static bool IsCurrentAppInDebugMode()
+    {
+        if(_isValueAlreadyValidated)
+        {
+            return _isInDesignMode;
+        }
+
+        _isInDesignMode = (bool)(DesignerProperties.IsInDesignModeProperty.GetMetadata(typeof(DependencyObject))?.DefaultValue ??
+            false);
+
+        _isValueAlreadyValidated = true;
+
+        return _isInDesignMode;
+    }
+
+    /// <summary>
+    /// Gets a value indicating whether the project is currently debugged.
+    /// </summary>
+    public static bool IsDebugging => System.Diagnostics.Debugger.IsAttached;
+
+    /// <summary>
+    /// Gets a value indicating whether the project is currently in design mode.
+    /// </summary>
+    public static bool IsInDesignMode => IsCurrentAppInDebugMode();
+}