Fixes:
- Real-time updates work again. The cloud sends a device notification's serial number as
data.message.deviceSn(the official integration adapted on 2026-08-27), and this integration still readdata.deviceSn- so once 1.3.0 got the websocket connection accepted, every device update failed to parse and only the 30-second polling kept things moving. Both spellings are accepted now. Found and first fixed by @MadDirtMonkey in #40, verified on live AP300/APEX 300 messages (#42).