Add UpdateObjectProcedureValidator with validation rules

Introduced UpdateObjectProcedureValidator using FluentValidation to enforce constraints on UpdateObjectProcedure fields, including ID checks and maximum length restrictions on various properties and nested objects.

src/ReC.Application/Common/Validations/UpdateObjectProcedureValidator.cs

@@ -0,0 +1,48 @@
+using FluentValidation;
+using ReC.Application.Common.Procedures.UpdateProcedure;
+
+namespace ReC.Application.Common.Validations;
+
+public class UpdateObjectProcedureValidator : AbstractValidator<UpdateObjectProcedure>
+{
+    public UpdateObjectProcedureValidator()
+    {
+        RuleFor(x => x.Id)
+            .GreaterThan(0)
+            .WithMessage("Target GUID/ID must be greater than 0.");
+
+        RuleFor(x => x.ChangedWho)
+            .MaximumLength(50)
+            .When(x => x.ChangedWho != null);
+
+        When(x => x.Endpoint is { Description: not null }, () =>
+        {
+            RuleFor(x => x.Endpoint.Description)
+                .MaximumLength(250);
+        });
+
+        When(x => x.EndpointAuth is { Description: not null }, () =>
+        {
+            RuleFor(x => x.EndpointAuth.Description)
+                .MaximumLength(250);
+        });
+
+        When(x => x.Profile is { Name: not null }, () =>
+        {
+            RuleFor(x => x.Profile.Name)
+                .MaximumLength(50);
+        });
+
+        When(x => x.Profile is { Mandantor: not null }, () =>
+        {
+            RuleFor(x => x.Profile.Mandantor)
+                .MaximumLength(50);
+        });
+
+        When(x => x.Profile is { Description: not null }, () =>
+        {
+            RuleFor(x => x.Profile.Description)
+                .MaximumLength(250);
+        });
+    }
+}