System Theme toggle

[ghostdevv]

When you first open docus it uses your system theme, and so toggling that works. However, as soon as you press the theme button then you can no longer get back to the system them behavior without clearing site data. It would be nice the button also let you choose system theme

[BittuBarnwal7479]

I'd be happy to investigate this if no one is already working on it. I originally ran into the issue while working on npmx-dev/npmx.dev#2880.