Function render_session 

pub fn render_session(outcome: &Outcome, when: &str, style: &Style) -> String

The session file.

A header a person reads, then one entry per kept idea in the follow-up queue’s shape, so parse_session and spar followup --file both read it back. Two rules keep that true and the tests hold them: no ## line other than an idea’s title, and nothing after the last idea, which is why the ideas set aside are listed in the header rather than at the end.