Color palettes

[uncenter]

Would like to revisit #200, but I can't comment on it to get it reopened so I'll just copy it here.

The default themes don't use hex codes, but rather colors like "red" and "lightyellow". It would make it a lot easier for people to make their own simple color palette themes, keeping the choice of blue for this component or whatever, but allowing them to use their own shades of that color.

[palette]
red = "#80AEFA"
green = "#CD9EFC"
white = "#FFA577"

https://starship.rs/ has this kind of thing, e.g. https://github.com/catppuccin/starship/blob/e99ba6b210c0739af2a18094024ca0bdf4bb3225/starship.toml#L23-L133. They support arbitrary color names too, which should ideally be the case here as well.

[sxyazi]

What is its behavior under light and dark modes respectively? Specifically, can users use different color palettes for light and dark modes? If so, how can this be supported? If not, why?

[uncenter]

In the theme.toml light/dark could be supported by:

[palette.light]
red = "#80AEFA"
green = "#CD9EFC"
white = "#FFA577"

[palette.dark]
...

Or/in addition to that a palette could be used in flavor.toml (just the palette, nothing else) and then put under flavor.dark or flavor.light in the theme.toml like how flavors are used.