Support RockBase IoT NM-EPD-420-4C with EP42YR_400x300 panel

[RockBase-iot]

Adds full device support for the NM-EPD-420-4C:

• Reuses the esp32-s3-N16R8 environment with 400×300 B/W/R/Y full-refresh support.
• Adds panel mapping, GPIO, button, battery, and deep-sleep wake configuration.
• Supports wake-time temperature and humidity sampling via AHT20.
• Adds low-power peripheral initialization, device configuration, preset data, and a factory firmware image.
• Partial refresh remains disabled for the four-color panel.

Verified on hardware: display refresh, physical buttons, BOOT wake, and battery reporting.

Tested with Home Assistant. The AHT20 need change the sensor.py to support sensor_type = 7 for AHT20.