[Imprv] Redesign Entity class to have meta checks for subclass creation in order to enable common methods in entity class

[bhati-pradeep]

Describe the request Redesign Entity class in such a way that it can have validation for sub class creation. Currently and in future, many common methods will be added due to common schemas in PC entities. New methods needs to be added to Entity class which can be used by all sub classes. So for this kind of use cases, we need to have some validations in Entity class which would check for certain properties required to create sub class out of it for every PC entity.

[bhati-pradeep]

Suggestion: Add method in entity class to create reference spec which is widely used across all modules as per entity subclass kind