00a33c227b
CI / changes (pull_request) Successful in 2s
CI / unit (pull_request) Successful in 9s
CI / integration (pull_request) Successful in 13s
CI / ui (pull_request) Successful in 49s
CI / gate (pull_request) Successful in 0s
CI / deploy (pull_request) Successful in 1m5s
DeleteMessage/EditMessage acted on the message id without checking it belonged to the campaign id in the URL. A mismatched pair could edit an unrelated campaign's message or — worse — delete the default campaign's last message via another campaign's URL, bypassing the "default keeps >=1 message" guard. Both now load the campaign and return ErrNotFound unless it owns the message (MoveMessage already did). Operator-only, but a real business-logic bypass. Regression test: TestBannerMessageOwnership.