feat(can/rx): MCP2515 CAN RX interrupt thread for ECU ID 0x50
- can_bus.h: add can_ecu_status_t struct + can_bus_get_ecu_status() declaration
- can_bus.c: add gpio_interrupt_init() (gpio sysfs, falling-edge poll)
- can_bus.c: add can_rx_thread() - poll gpio63 INT pin, parse 0x50 frame
(throttle_status, pedal_volt, led_flash_timer, can_lose_ecu, throttle_limit_off, heart_beam)
with CAN_LOSE timeout detection (100ms)
- can_bus.c: start/join can_rx thread in can_bus_init()/can_bus_close()
- can_bus.c: add can_bus_get_ecu_status() thread-safe snapshot
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
miketsai
fd54f5cc0b