Follow conversations as they change

Without cursor: the cursor for changes from now on (list the conversations after this call). With it: every conversation whose shown state, or your own marks of it (seen_at, dismissed_at), changed since, each once, oldest change first. Send Prefer: wait=<seconds> (up to 20) to hold an empty answer until something changes. Scope: project_id, else an API key’s project; a signed-in person without project_id follows every project they work in (organization_id narrows it to one organization).