Dark theme via DarkReader

[donfiguerres]

Issue

Closes #59

Description

Use DarkReader as a darkmode provider.
I've added the option to use other theme color providers and hopefully toha's own dark theme in the future. This possible with the darkTheme.provider property. Below is an example on how to set-up the dark theme. I'm also planning to add this information to the toha documentation.

# Dark theme toggle
darkTheme:
  provider: darkreader
  enable: true
  default: dark

The drawback of this is that it is a lot slower than having your own dark theme because the theme is dynamically generated.

Test Evidence

It's already live in my website https://donfiguerres.com/

[hossainemruz]

Hi @donfiguerres, Thank you for the amazing work. I have added few comments. Can you please acknowledge them. Otherwise, looks good to me.

[donfiguerres]

Hi @donfiguerres, Thank you for the amazing work. I have added few comments. Can you please acknowledge them. Otherwise, looks good to me.

Thanks for the feedback! I agree with your inputs. I'll work on these and push the changes to my branch.

[donfiguerres]

Done with the changes and already live on my website at https://donfiguerres.com/ if you need to see how it looks.

I also did a quick test with the multilingual mode to make sure it doesn't conflict with the language dropdown menu.

[hossainemruz]

Hi @donfiguerres, thanks again for the hard work. Looks good to me. I will test and merge soon.