Refactor JpaEntityInformation handling in repository.query and repository.support packages #4037
Description
JpaEntityInformation is a central piece of information that we use across our repository and query implementations. We have to determine consistently an entity name that might come from XML (and not only @Entity), determine identifier columns and obtain the keyset for a given object.
Right now, we have several tangles and inconsistencies (e.g. if a domain class is not an EntityType, usages from JpaKeysetScrollQueryCreator in the query package). Ideally, all related information would reside inside JpaPersistentEntity or a similar type that we can put next to JpaPersistentEntity to unify identifier access (JpaPersistentEntityImpl and JpaMetamodelEntityInformation deal with identifiers and both in different ways).