alexei.dolgolyov
7c0c064453
The GET /devices/{id}/brightness endpoint was making an HTTP request to
the ESP32 over WiFi on every frontend poll (~3s), causing 150ms async
event loop jitter that froze the LED processing loop. Cache brightness
server-side after first fetch/set, add frontend dedup guard, reduce
get_device_info() frequency, and add processing loop timing diagnostics.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>