Better support for JSON

[petermarks]

This theme doesn't seem to do much for JSON, everything seems to be blue:

On GitHub, it still isn't great, but there is more variation:

Any interest in addressing this?

I'd be happy to look into implementing it, but have no experience with developing themes in Zed or other editors. I can see that themes are JSON files with hex color values, but how do you find out what tags are used for each syntactic element and how do you test changes to themes?

[PyaeSoneAungRgn]

I reference VSCode Github Theme for syntactic. You can test themes changes easily by overriding theme https://zed.dev/docs/themes#theme-overrides. Feel free to send PR.