f87e4c0d6b
Generalise printer-only monitoring to every configured device. New DeviceMonitor polls all enabled devices each tick (default 8s): printers via rich readStatus(), relays/readers/cameras via the generic healthCheck() reachability probe, flattened to one traffic-light (ready/degraded/offline) + detail, deduped (emit on change only), fail-toward-offline. - device-status bus event + GET /api/devices/status snapshot. - Pushed over the existing /api/ws (hello carries the initial set; device-status frame per change). - Web: live-store devices map, WS handler, DeviceFooter chip-per-device (role label not vendor; click a degraded/offline chip for an issues panel). Verified roleKind resolution + change-only emit on a fresh DB. Note: the footer's UI surface (api type, router mount, i18n devices) rides in the subsequent subscription commit due to shared-file overlap. Claude-Session: https://claude.ai/code/session_01Xcm6ikLgGoCxxHrxtjkk5V