systutils/aoostar-rs: AOOSTAR WTR MAX / GEM12+ PRO LCD screen control tool

asterctl is an open-source tool to control the embedded LCD screen of the
AOOSTAR WTR MAX and GEM12+ PRO mini PCs.

Features:

• Switch the secondary display on or off
• Display custom images (auto-scaled to 960x376, RGB565)
• Render dynamic sensor panels compatible with AOOSTAR-X config files
• Partial screen update support for fast refresh
• USB device/serial port selection

The LCD screen communicates over USB UART (vendor ID 0x0416, product ID
0x90A1). On FreeBSD the device appears as /dev/cuaU0 (requires the umodem
kernel module).

All protocol commands have been reverse engineered from the original
AOOSTAR-X Windows software. No official documentation is available.