Enums to pointer to enums

[ThePedroo]

Describe the feature

This feature request is to the change of pure enums to pointer to enums.

Acceptance criteria

• All enums of structures of gencodecs must use pointer to enums instead.

Additional context

Concord has been using enums for some time, and they have some issues when it comes to identifying whether or not the field was provided, as they would always default to 0. Especially in cases to send requests, where the enum field is nullable, it would be problematic.