This is a very minor nitpick, but the Pico C/C++ documentation PDF (https://datasheets.raspberrypi.com/pico/raspberry-pi-pico-c-sdk.pdf) has a code example in section 10.4 ("Including Binary Information pages") on page 590 that uses GPIO_FUNC_PROC, which is not defined anywhere.
It looks like that's an old name for the enum constant GPIO_FUNC_SIO, and the PDF wasn't updated when the renaming happened.
Instead of correcting GPIO_FUNC_PROC to GPIO_FUNC_SIO, I think it would make more sense to replace the whole line
gpio_set_function(LED_PIN, GPIO_FUNC_PROC);
 
with