tcloud compatibility, dotnet bug fixes

enterprise/SingleOrArrayConverter.cs

@@ -0,0 +1,29 @@
+using System;
+using System.Collections.Generic;
+using System.Text.Json;
+using System.Text.Json.Serialization;
+
+namespace TrainSearchWorker.Converters
+{
+    public class SingleOrArrayConverter<T> : JsonConverter<List<T>>
+    {
+        public override List<T> Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options)
+        {
+            if (reader.TokenType == JsonTokenType.StartArray)
+            {
+                return JsonSerializer.Deserialize<List<T>>(ref reader, options) ?? new List<T>();
+            }
+            else
+            {
+                // Single element – wrap it in a list.
+                T element = JsonSerializer.Deserialize<T>(ref reader, options);
+                return new List<T> { element };
+            }
+        }
+
+        public override void Write(Utf8JsonWriter writer, List<T> value, JsonSerializerOptions options)
+        {
+            JsonSerializer.Serialize(writer, value, options);
+        }
+    }
+}