Function is_meta_commit 

pub fn is_meta_commit(subject: &str) -> bool

Whether subject matches a known engine/meta commit template.

Subject templates are SPOOFABLE by a worker’s own git commit, so this alone must never exempt a commit from the deliverable count or the path sweep — use is_meta_commit_with_paths wherever the commit’s changed paths are available (the orchestrator’s sweep and final gate both do).