fn looks_like_rollout_id(s: &str) -> boolExpand description
LOADBEARING: validates the canonical RFC-0008 §6.3 RolloutId shape
"{channel}@{channel_ref}" and blocks path-traversal smuggling
(/, .., whitespace, multi-@ all fail the character classes).
Channel is locked to lowercase ASCII to match the cycle’s convention
and avoid case-insensitive-filesystem collisions on macOS hosts; the
ref tracks the git SHA shape upstream of the producer.