RcLights

Reads steering, throttle and a switch from a receiver and drives park and driving light, tail and brake light, reversing light, two turn signals and an auxiliary output. The turn signals only trigger after the steering has been centred for a moment, so cornering indicates and line corrections do not; the brake and reverse logic follows the ESC you actually have. Channel 3 is a two- or three-position switch whose positions you assign to hazards, an auxiliary output or a light switch. The decision logic is plain C with no Arduino dependency and is covered by host tests; the Arduino layer only measures pulses and writes PWM. Builds for AVR, ESP32 and STM32, and its pin capture works on all three -- on AVR it brings its own pin-change interrupts, because two external interrupt pins are one short of three channels.