btcpayserver/BTCPayServer/WellKnownTempData.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;

namespace BTCPayServer
{
    public class WellKnownTempData
    {
        public const string SuccessMessage = nameof(SuccessMessage);
        public const string ErrorMessage = nameof(ErrorMessage);
    }
}