v0.1.20

What's new

State bounce fix - After sending a command via MQTT (e.g. turning off the chlorinator), the UI no longer flips back to the old state.

AWS IoT echoes back an intermediate shadow update immediately after a write, but the reported section still reflects the old device state (the device has not processed the command yet). That stale update is now ignored during the 5-second post-write settling window, so the optimistic state stays correct until the device confirms the change.