Why: API-key issuance shares the account maintenance no-create and credential-output contract; the old CLI printed its key and lacked --out-file.
Evidence: The new subprocess test failed before the flag existed, then passed for private output and pre-mutation collision refusal; current go vet and all Go tests pass.
Impact: apikey create accepts protected --dsn-file and --out-file, preserves stdout default, and never overwrites an existing destination.
Refs: Backend PR #185; Dev PR #486; U7 KTD14