Native test suite (61 tests, 5 suites) with thin mock layer for
Arduino/FreeRTOS/esp_timer enabling host-side testing without hardware.
ASCOM Alpaca REST API on port 32323 with UDP discovery, implementing
Telescope v3 interface for N.I.N.A., PHD2, and compatible software.
Follows existing ST4WiFi conditional compilation pattern.
README documents wiring, all three protocols (serial, WebSocket, Alpaca),
pin/rate configuration, and build instructions.
