ISO 8601 timestamp. Omitted entirely when not supplied — the sidecar is
content-addressed by the two model digests, not by when it was written,
and stamping Date.now() by default would make two runs over the same
pair produce different bytes for no reason.
ISO 8601 timestamp. Omitted entirely when not supplied — the sidecar is content-addressed by the two model digests, not by when it was written, and stamping
Date.now()by default would make two runs over the same pair produce different bytes for no reason.