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LanMountainDesktop/Models/AppSettingsSnapshot.cs

@@ -116,6 +116,8 @@ public sealed class AppSettingsSnapshot
 
     public int StatusBarCustomSpacingPercent { get; set; } = 12;
 
+    public bool EnableThreeFingerSwipe { get; set; } = false;
+
     public List<string> DisabledPluginIds { get; set; } = [];
 
     #region Study Settings

LanMountainDesktop/Models/FusedDesktopLayoutSnapshot.cs

@@ -0,0 +1,96 @@
+using System;
+using System.Collections.Generic;
+
+namespace LanMountainDesktop.Models;
+
+/// <summary>
+/// 融合桌面组件放置快照 - 用于在系统桌面（负一屏）上放置组件
+/// </summary>
+public sealed class FusedDesktopComponentPlacementSnapshot
+{
+    /// <summary>
+    /// 放置实例ID（唯一标识）
+    /// </summary>
+    public string PlacementId { get; set; } = string.Empty;
+    
+    /// <summary>
+    /// 组件类型ID
+    /// </summary>
+    public string ComponentId { get; set; } = string.Empty;
+    
+    /// <summary>
+    /// X 坐标（像素，相对于屏幕左上角）
+    /// </summary>
+    public double X { get; set; }
+    
+    /// <summary>
+    /// Y 坐标（像素，相对于屏幕左上角）
+    /// </summary>
+    public double Y { get; set; }
+    
+    /// <summary>
+    /// 宽度（像素）
+    /// </summary>
+    public double Width { get; set; } = 200;
+    
+    /// <summary>
+    /// 高度（像素）
+    /// </summary>
+    public double Height { get; set; } = 200;
+    
+    /// <summary>
+    /// Z-Index（用于控制组件层叠顺序）
+    /// </summary>
+    public int ZIndex { get; set; }
+    
+    /// <summary>
+    /// 是否锁定位置（锁定后不可拖动）
+    /// </summary>
+    public bool IsLocked { get; set; }
+    
+    /// <summary>
+    /// 创建深拷贝
+    /// </summary>
+    public FusedDesktopComponentPlacementSnapshot Clone()
+    {
+        return new FusedDesktopComponentPlacementSnapshot
+        {
+            PlacementId = PlacementId,
+            ComponentId = ComponentId,
+            X = X,
+            Y = Y,
+            Width = Width,
+            Height = Height,
+            ZIndex = ZIndex,
+            IsLocked = IsLocked
+        };
+    }
+}
+
+/// <summary>
+/// 融合桌面布局快照 - 包含所有在系统桌面上显示的组件
+/// </summary>
+public sealed class FusedDesktopLayoutSnapshot
+{
+    /// <summary>
+    /// 是否启用融合桌面功能
+    /// </summary>
+    public bool IsEnabled { get; set; }
+    
+    /// <summary>
+    /// 组件放置列表
+    /// </summary>
+    public List<FusedDesktopComponentPlacementSnapshot> ComponentPlacements { get; set; } = [];
+    
+    /// <summary>
+    /// 创建深拷贝
+    /// </summary>
+    public FusedDesktopLayoutSnapshot Clone()
+    {
+        return new FusedDesktopLayoutSnapshot
+        {
+            IsEnabled = IsEnabled,
+            ComponentPlacements = [.. ComponentPlacements.ConvertAll(p => p.Clone())]
+        };
+    }
+}