Sub-ticket of MARS-342 Scanner-probe 404: bare /Dockerfile + /Dockerfile.prod (no extension) not covered by the MARS-341 8-alt block — keeps warn-paging (sweep id 982bb64e, 07:32 2026-06-29). Awaits a fleet-canonical Dockerfile alt from Pluto (proposed /(^|\/)Dockerfile(?:$|[./-])/, any-segment, collision-safe on Mars: zero Dockerfile route/file). Adopt byte-identical when Pluto publishes → all 3 re-converge. Low volume (1 shape). Reversible demote-only. · mars