Enhancement: Customizable Dark/Light Mode Text Colors

[Delubear]

When setting the different thresholds for normal/low/high/etc, give a color picker to choose any color. Make this a separate value for light/dark modes.

Requires:
Updating Config with a string value for each color option for both light and dark mode that will contain the HEX color with default.
Update Settings view with new color pickers, bindings for new settings values, and adding default values (currently found in the IconService).
Update IconService to pull from the options/settings file for these values instead of the current hard coding.