Opt-in per workflow via a YAML comment; no comment = unchanged behaviour for every repo. Marker-less pushes spawn no runner at all (no run queue, no waste). Added for ariki-game sim-publish-staging (Ozan: deploys are explicit). Co-Authored-By: Ozan Bozkurt <ozan@tinqs.com> Co-Authored-By: ZCode GLM-5.3-Flash <agents@tinqs.com>