Add LightbulbStyle

[ykrx]

A minimal dark theme based on the Lightbulb theme for VSCode.

[Anteru]

Thanks for the contribution! Unfortunately, your style doesn't pass the WCAG recommendation for contrast, is there any chance you can bump the contrast? Dark theme or not, we do want to maintain some level of accessibility, and often times only small tweaks are needed to get there.

[jeanas]

Looks good, thanks:

[numist]

This PR says merged but I don't see anything matching eclipse in the output of get_all_styles()… what is the name of this new style?

[jeanas]

“lightbulb”

[numist]

Oops, I'd intended to write this in #2440, which I now see was declined.

So only one new style for 2.16.0 then?

[jeanas]

FWIW, #2240 wasn't declined, but somehow the author decided (for reasons that are not clear to me) to close the PR and even delete the source branch.

[numist]

Sorry I didn't mean to imply who declined the PR, just the general term used in my parts.

Too bad; new themes are fun.