modular_aphelion/modules/custom_sprites/code/persistence.dm

/datum/json_savefile/custom_sprites	The account's drawing sidecar, custom_sprites.json beside preferences.json, with verified writes and a recovery backup.
/proc/custom_sprite_sidecar_path	The drawing sidecar beside a preferences.json path, or null when the path has no directory.
/proc/custom_sprites_after_import	Imports replace the character identities, so an old slot's drawings cannot carry across.