Add support for TV garden

Checklist

• I am aware that this issue is being opened for the NewPipe Extractor, NOT the app, and my feature request will be dismissed otherwise.
• I made sure that there are no existing issues - open or closed - which I could contribute my information to.
• I have taken the time to fill in all the required details. I understand that the feature request will be dismissed otherwise.
• This issue contains only one feature request.
• I have read and understood the contribution guidelines.

Feature description

Add support for TV garden which is website that allows you to watch TV channels from the world.

Why do you want this feature?

This feature will allow people to watch TV easier. TV garden also doesn't have an app, so you can add it to NewPipe.

Additional information

TV channels on this websites are technically LIVE videos, so they can be supported in similar way to YouTube LIVES. Some of them are YouTube LIVES, so they can just open like normal YouTube LIVES. Countries can render as channels or as sub-channels of continents like in PeerTube and cattegories can render in same place as "Top 50" and "New and popular" in SounCloud.
Website adress: https://tv.garden/

Start with the linked TV Garden website and review the NewPipeExtractor repository's existing site-support entry points; the issue names no file or test. Done means TV Garden channels, countries or continent groupings, categories, and live streams are supported by the extractor as described.