Add primitive visual property

DataAccess/DTOs/DTOEntities/BeamShears/StirrupGroupDTO.cs

@@ -1,5 +1,8 @@
 using Newtonsoft.Json;
+using StructureHelperCommon.Models.VisualProperties;
 using StructureHelperLogics.Models.BeamShears;
+using StructureHelperLogics.NdmCalculations.Primitives;
+using System.Windows.Media;
 
 namespace DataAccess.DTOs
 {
@@ -8,20 +11,27 @@ namespace DataAccess.DTOs
         [JsonProperty("Id")]
         public Guid Id { get; }
         [JsonProperty("Name")]
-        public string? Name { get; set; }
+        public string? Name { get; set; } = string.Empty;
         [JsonProperty("CompressedGap")]
-        public double CompressedGap { get; set; }
+        public double CompressedGap { get; set; } = 0;
         [JsonProperty("Stirrups")]
         public List<IStirrup> Stirrups { get; } = new();
+        [JsonProperty("VisualProperty")]
+        public IPrimitiveVisualProperty VisualProperty { get; set; }
+
         public StirrupGroupDTO(Guid id)
         {
             Id = id;
+            VisualProperty = new PrimitiveVisualPropertyDTO(Guid.NewGuid())
+            {
+                Color = (Color)ColorConverter.ConvertFromString("Black")
+            };
         }
 
 
         public object Clone()
         {
-            throw new NotImplementedException();
+            return this;
         }
     }
 }