options: Make form controls respect color scheme

[ator-dev]

• I agree to license my code under the MPL 2.0 license.
• I rebased my work on top of the main branch.
• I ran npm test and all tests passed.
• I added test coverages if relevant.

I don't think this needs to be tested; it's only aesthetic.

Description

Every time I used the options I had the feeling something was off with the colours, and I just realised what it is. The color-scheme property isn't set, so the form controls default to light theme even if everything else is dark! I have set it to light dark at the root level, which means all UI chrome respects the user's colour preference, with "light" being the default.

https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Properties/color-scheme

Type of change

• Bug fix
• New feature
• Major change (fix or feature that would cause existing functionality to work differently than in the current version)

Tag issues related to this pull request:
None (I think)