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).
MetricsModule is a C++ class designed for collecting and sending metrics data from an ESP32-based device. The module supports buffering metrics in JSON format and sending them to a specified database URL. It integrates with FreeRTOS for task management and leverages ESP-IDF for network and logging capabilities.