add statuscode to apiexception

Pilz.Net/Api/ApiException.cs

@@ -1,11 +1,20 @@
-namespace Pilz.Net.Api;
+using System.Net;
+
+namespace Pilz.Net.Api;
 
 public class ApiException : Exception
 {
+    public HttpStatusCode StatusCode { get; }
+
     public ApiException()
     {
     }
 
+    public ApiException(string? message, HttpStatusCode statusCode) : base(message)
+    {
+        StatusCode = statusCode;
+    }
+
     public ApiException(string? message) : base(message)
     {
     }