结构调整，便于后续扩展

AIStudio.Wpf.Flowchart/Models/FlowNodeDesignerItem.cs

@@ -0,0 +1,51 @@
+using AIStudio.Wpf.Flowchart.ViewModels;
+using Newtonsoft.Json;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using System.Windows.Media;
+using System.Xml.Serialization;
+using Util.DiagramDesigner;
+
+namespace AIStudio.Wpf.Flowchart.Models
+{
+    public class FlowNodeDesignerItem : DesignerItemBase
+    {
+        public FlowNodeDesignerItem()
+        {
+
+        }
+        public FlowNodeDesignerItem(FlowNode item) : base(item)
+        {
+            if (item is MiddleFlowNode middleFlow)
+            {
+                UserIds = middleFlow.UserIds;
+                RoleIds = middleFlow.RoleIds;
+                ActType = middleFlow.ActType;
+            }
+            Color = item.Color;
+            Kind = item.Kind;
+            StateImage = item.StateImage;
+        }
+
+        [XmlArray]
+        public List<string> UserIds { get; set; }
+
+        [XmlArray]
+        public List<string> RoleIds { get; set; }
+
+        [XmlAttribute]
+        public string ActType { get; set; }
+
+        [XmlAttribute]
+        public string Color { get; set; }
+
+        [XmlAttribute]
+        public NodeKinds Kind { get; set; }
+
+        [XmlAttribute]
+        public string StateImage { get; set; }
+    }
+}