SCADABLE platform integration for ESP32. Boots, loads the
device certificate from NVS, discovers the MQTT broker via
edge.scadable.com, connects over TLS, publishes heartbeats,
and handles OTA updates. Optional streaming file upload to
uploads.scadable.com (compile-time opt-in). Customer brings
their own network (Wi-Fi / Ethernet / cellular).
This is a client for dynamic DNS services, aimed at ESP (ESP32, etc) devices. Your node can use such a service to make its IP address known as a public DNS name, so you can find it, and use it from applications.