Thank you!! We had a lot of fun making it and are continuing to develop it outside of the jam.
As for your stuck problem, you could try teleporting. If you press "i" and open up the info screen, then click on the Teleport tab, you'll find that you should be able to teleport back to Terra Island.
Viewing post in Dragon Fields jam comments
I will try again if I do fall off the cliff (hopefully not!)! In the end, I ended up deleting my game and starting over again. I actually fell into the river once, and managed to get out by using the spacebar. By this point my dragons could fly and I checked the help menu again and saw that the spacebar can be used for both ascending and jumping, so I gave it a try and it worked! So this might also be another solution!