Function write_take 

fn write_take(take_dir: &Path, take: &TakeRecord<'_>) -> bool

One claimed take’s files, meta.json last, answering whether the take was written whole.

A failure stops this take’s write and leaves a partial directory, which never reads as a complete take; capture_take then skips the prune. An abandoned take is taken back by capture_take when its token is set by the time this returns.