Styling: Add `.destructive` class for `button.text-button`

[wpkelso]

Image excluded for now because I don't believe there is a precedent style.

[danirabbit]

I don't think this works in the dark style:

Compared to the old stylesheet:

[wpkelso]

@danirabbit Ah, you're right, I totally didn't check that. Should probably just use SILVER_100 foreground for both cases? I'm afk right now so I can't verify that provides sufficient contrast for dark mode as well, but if it doesn't then we might need to modify the dark mode error color

[danirabbit]

@wpkelso in the old stylesheet we just use white