Replace the dual-switch handler with one button: short press cycles patterns, long press arms deep sleep with ext1 GPIO wake. Add a heartbeat LED task and fix the IMU test I2C pins to GPIO21/GPIO6. Co-authored-by: Cursor <cursoragent@cursor.com>
Replace the dual-switch handler with one button: short press cycles patterns, long press arms deep sleep with ext1 GPIO wake. Add a heartbeat LED task and fix the IMU test I2C pins to GPIO21/GPIO6. Co-authored-by: Cursor <cursoragent@cursor.com>