Add nullable support

src/Prospect.Server.Api/Models/Client/FAddGenericIDRequest.cs

@@ -5,6 +5,9 @@ namespace Prospect.Server.Api.Models.Client;
 
 public class FAddGenericIDRequest
 {
+    /// <summary>
+    ///     Generic service identifier to add to the player account.
+    /// </summary>
     [JsonPropertyName("GenericId")]
-    public FGenericServiceId GenericId { get; set; }
+    public FGenericServiceId GenericId { get; set; } = null!;
 }