- Add delete-listing.handler.spec.ts: not-found, forbidden, owner happy path, admin override, tx rollback propagation, call ordering. - Annotate DeleteListingHandler with the repository atomicity contract; PrismaListingRepository.delete already wraps side-effects in prisma.$transaction([...]) so handler stays a thin orchestrator. Co-Authored-By: Paperclip <noreply@paperclip.ing>