Function append_transcript_lines 

fn append_transcript_lines(
    fs: &Arc<FileStore>,
    zone: &str,
    name: &str,
    data: &[u8],
    stamp: bool,
    what: &str,
) -> Option<AppendPos>

append_lines on a transcript file, creating it on first write (or if another instance deleted it since). Whole non-blank lines only: a torn last line is closed, not continued (filestore/counter.rs). With stamp, the output.tsidx receive-time record is written in the same transaction (one commit, not two). Errors are logged and swallowed.