[Util Change]: Issue about coping and pasting hex value in gradient generator

### Util Name

gradient-generator

### Changes

The value of hex in the color picker cannot be copied or pasted, which is very annoying because you have to type those values by hand.
The same problem occurs with RGB and HSL. Moreover, the majority of plugins use hex values to color text, so I think it would be nice if hex appeared first in the color picker. Currently, you have to switch from RGB to HSL and from HSL to hex. I know it's only two clicks, but when you're coloring every message in a config file, it becomes exhausting.

### Extra Info

_No response_