This task lists all possible follow-ups cleanups/refactors after recent switch to IDTypeInfo system for ID management. Note that some may require their own tasks, if they are not trivial and/or require some design work first.

• Cleanup code used during transition from old system to new one
• Make BKE_lib_id_swap and BKE_libblock_get_alloc_info generic.
• Move utils from BKE_idcode to BKE_idtype and remove the former (rB12b621059a6f1337e).
• Add new callback in IDTypeInfo for libquery and move all ID types to it (this might be less trivial than it looks like).

Note: read/write of blend file refactoring is handled in a different task, T76372.