Room light survey
What it does
Walks the user through a short camera sweep of the room and reports one of four bands, from "low" to "direct sun."
Why a band
A phone camera cannot justify a precise figure, and a precise-looking number would be trusted more than it deserves (decisions.md → 2026-07-14).
Known limit
Agreement with a real lux meter is unverified across handsets. That is Open Questions §1 and the queued sensor accuracy sweep.