Refactor: add TODOs for generic repository pattern

Added TODO comments in ICatalogRepository and CatalogRepository to suggest adopting a generic repository pattern to reduce code duplication. Also noted the potential move of the interface to the application layer for better adherence to clean architecture principles.

DbFirst.Domain/Repositories/ICatalogRepository.cs

@@ -2,6 +2,8 @@ using DbFirst.Domain.Entities;
 
 namespace DbFirst.Domain.Repositories;
 
+// TODO: instead of creating interface per entity, consider using generic repository pattern (eg. IRepository<T>) to reduce code duplication.
+//TODO: move to application layer as a part of clean architecture
 public interface ICatalogRepository
 {
     Task<List<VwmyCatalog>> GetAllAsync(CancellationToken cancellationToken = default);