Вытащил солюшен на уровень выше, чтобы прощё было дотнетить

ApplicationLayer/Services/Users/Requests/Validation/ChangeUserAuthDataRequestValidator.cs

@@ -0,0 +1,23 @@
+using Domains;
+using FluentValidation;
+
+namespace ApplicationLayer.Services.Users.Requests.Validation;
+
+public class ChangeUserAuthDataRequestValidator : AbstractValidator<ChangeUserAuthDataRequest>
+{
+    public ChangeUserAuthDataRequestValidator()
+    {
+        RuleFor(r => r.UserId)
+            .NotEmpty();
+
+        RuleFor(r => r.NewAuthData)
+            .NotEmpty();
+
+        RuleFor(r => r.NewAuthData.Email)
+            .NotEmpty()
+            .EmailAddress()
+            .WithMessage("Email should be valid")
+            .MaximumLength(ConfigurationConstraints.EmailLength)
+            .WithMessage($"Email address length must be less than {ConfigurationConstraints.EmailLength}");
+    }
+}