Improve contrast and readability with light theme

[flodolo]

Fixes #4206

[codecov-commenter]

Codecov Report

❌ Patch coverage is 45.45455% with 6 lines in your changes missing coverage. Please review.
✅ Project coverage is 81.00%. Comparing base (6727ff3) to head (2fbf8a8).

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[flodolo]

I left a temporary folder with screenshots. If you look at the last commit 1bcb33d (this PR) you should be able to use the Swipe mode to see the difference before/after.

Mostly:

• Darker gray and green for translation statuses
• Darker gray for disabled chart categories (now almost invisible)
• Also fixed theme switching on charts

[ayshushus]

i like it alot! just a few things:

between light and system, the bar is missing (happened in my PR as well 😅):

error color is lighter here:

and here:

would we want to make the greens similar? here for example:

i think we should change this, RGB is still off, it's a fuzzy string, e.g. /af/amo/LC_MESSAGES/djangojs.po/?extra=fuzzy&string=190758

[flodolo]

Thanks for the review. Turns out I'm introducing inconsistency in a ton of places.

Setting this back to draft, and running locally a bit longer.

[flodolo]

I'm going to close this PR to avoid noise, and likely open one from a different branch when I feel it's ready.

At this point I'm making several design choices on color, so it might require a different discussion.