character-sheet

There's no errors, and the UI works fine, but when you hit save, it reverts back to the previous color.

As you can see, the color is being sent correctly:

But the return value contains the previous color:

![image](https://user-images.githubusercontent.com/770655/155006278-19bb5

For inputs that can have parse errors (like a number that must be from 0 to 20), highlight the field on error, and provide some way to view an error message (eg. "Must be an integer", or "Number must be between 0 and 20").

TODO: find all the places that need this
TODO: make this general enough to work with most parsed text inputs