Enhance framework compatibility and code readability

Added preprocessor directives for .NET framework compatibility.
Modified `using` directives to be framework-specific.
Improved code formatting for better readability.
Introduced obsolete attributes for deprecated methods,
recommending `MediatR` as an alternative.
Added XML documentation for clarity and maintainability.

DigitalData.Core.Abstraction.Application/IBasicCRUDService.cs

@@ -1,4 +1,5 @@
-namespace DigitalData.Core.Abstraction.Application
+#if NET
+namespace DigitalData.Core.Abstraction.Application
 {
     /// <summary>
     /// Implements a simplified CRUD service interface that uses a single Data Transfer Object (DTO) type for all CRUD operations,
@@ -18,4 +19,5 @@
         where TDto : class where TEntity : class
     {
     }
-}
+}
+#endif