Add using directive.

Author: bitbound

ControlR.Web.Server/Program.cs

@@ -9,6 +9,7 @@
 using Scalar.AspNetCore;
 using System.Reflection;
 using ControlR.Web.Server.EndpointFilters;
+using ControlR.Libraries.Api.Contracts.Constants;
 
 var isOpenApiBuild = Assembly.GetEntryAssembly()?.GetName().Name == "GetDocument.Insider";
 var builder = WebApplication.CreateBuilder(args);