Issues and questions a desk finds go to a visible place, not into prose

In the voice-feedback signal, a finding (the page could not be found in the snapshot) was buried mid-page under a title that said nothing of it. Desks record findings as loose ends (data/loose-ends.json) or open questions (history/open-questions.md) and link them from the piece's byline ("2 findings"); the front page's Open rail counts them.

Done when: AUTHORING.md says so, the desks' prompts say so, and the byline shows the findings of a piece.