Fellow Godot person wooo
I've never done a Nurikabe puzzle before and I can confirm now I am very bad at them.
Small note: playing on a MacBook Pro, I think the resolution is kind of messed up (see picture). I have issues with my games where I have to turn off Allow HiDpi to make it look good on Mac. Of course this has downsides with rendering though. Hopefully later I will try this on my Windows machine to see how it looks.