Implement activation checks across various commands and queries

- Introduced `IRequiresActivation` interface to enforce activation requirements for multiple commands and queries, ensuring that only activated users can create, edit, or access configurations, news, and applications.
- Updated the `RequireActivationBehavior` to handle activation checks uniformly, returning appropriate errors for unauthenticated or inactive users.
- Enhanced error handling by adding `NotActivated` error to provide clear feedback for users attempting to access restricted features.
- Updated documentation to reflect the new activation requirements and their implications on user access and functionality.

backend/src/PnvPanel.Application/DependencyInjection.cs

@@ -22,9 +22,10 @@ public static class DependencyInjection
         RegisterClosedGeneric(services, assembly, typeof(IQueryHandler<,>));
         RegisterClosedGeneric(services, assembly, typeof(IValidator<>));
 
-        // Порядок важен: Logging (снаружи) -> Validation -> UnitOfWork (ближе к хендлеру).
+        // Порядок важен: Logging (снаружи) -> Validation -> RequireActivation -> UnitOfWork (ближе к хендлеру).
         services.AddScoped(typeof(IPipelineBehavior<,>), typeof(LoggingBehavior<,>));
         services.AddScoped(typeof(IPipelineBehavior<,>), typeof(ValidationBehavior<,>));
+        services.AddScoped(typeof(IPipelineBehavior<,>), typeof(RequireActivationBehavior<,>));
         services.AddScoped(typeof(IPipelineBehavior<,>), typeof(UnitOfWorkBehavior<,>));
 
         return services;