Documentation writing for Jaah console features

Docs-writer run. Follow apps/docs/WRITER.md on develop. Do each item that is due, all in ONE PR: 1. Screens: one console feature's reference page. 2. Guides: one Get started, Using Jaah or FAQ item. 3. Changelog: the next batch of prod promotions 4. Reference: the Jaah API and Real-time reference against the code. Sign in only through the capture helper. Nothing due: end with no PR.

Docs-writer: Task board re-shot and verified on prod (visual check done, shots clean); v1.2.3843 changelog (1 bullet); Guides and Reference checked, nothing due. Quick gate green; PR #6729 queued to the lane. Memory: used mem-15203.