This is a variation of the flow-managed data access pattern that:
- allocates a persistence context in conversation scope instead of flow scope
- flushes changes manually when requested, with flushing behavior also driveable by transition metadata
- all data access is non-transactional
- closes the persistence context when the conversation ends
This is appropriate for use when isolation from the DB is not desired; for example, for flushing changes to the DB after each view-state.