Audit Haven DSGS 2026 devices with ≥5-day telemetry gaps

Subtask of BOLT-1744. Grace requested read-only audit in #grace-and-bots, Slack message 1785974314.207919. Identify enrolled battery devices in Haven Energy 2026 DSGS (workspace program cmnxr4odu0005j2dacugqyk8j) whose latest telemetry is at least five days old or absent. Deliver a CSV in the request thread; no enrollment/device status changes.