The APFS reference (https://developer.apple.com/support/downloads/Apple-File-System-Reference.pdf) mentions APFS volume roles, in particular System, Recovery, Preboot etc. (APFS_VOL_ROLE_SYSTEM, APFS_VOL_ROLE_RECOVERY, APFS_VOL_ROLE_PREBOOT)
and I'm wondering what is the API function to query the role for a given APFS volume?