Decouple Wallet Send screen from Ledger Wallet

BTCPayServer/Models/WalletViewModels/WalletSendLedgerModel.cs

@@ -0,0 +1,15 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Threading.Tasks;
+
+namespace BTCPayServer.Models.WalletViewModels
+{
+    public class WalletSendLedgerModel
+    {
+        public int FeeSatoshiPerByte { get; set; }
+        public bool SubstractFees { get; set; }
+        public decimal Amount { get; set; }
+        public string Destination { get; set; }
+    }
+}