feat: get best trader offer for items

TODO: Make a better conversion for USD/EUR to RUB

Plugin/Structs/TradeOfferStruct.cs

@@ -0,0 +1,23 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace LootValueEX.Structs
+{
+    internal readonly struct TradeOfferStruct
+    {
+        internal readonly string TraderID;
+        internal readonly string CurrencyID;
+        internal readonly int Price;
+        internal readonly float PriceInRouble;
+        internal TradeOfferStruct(string traderId, string currencyId, int price, float priceInRouble)
+        {
+            TraderID = traderId;
+            CurrencyID = currencyId;
+            Price = price;
+            PriceInRouble = priceInRouble;
+        }
+    }
+}