List a newsletter's threads

The conversations in this newsletter's community, most recently active first, ordered by last_activity_at descending.

A credential holding only read permissions sees threads whose visibility is public. One holding write in any family on the newsletter also sees subscribers and paid threads, which are the ones a reader has to have joined the newsletter to read.

Threads opened by an article are included and carry is_article_thread as true. Filter them out with is_article_thread=false when you want only what people started themselves.