[FR]: Integrating the RSS aspect of Piped to Farside

[RetroAbstract]

This feature request is for integrating the RSS aspect of Piped to Farside.

Unlike Invidious, Piped uses the instance API URL for RSS feeds.

So with that in mind, for example if I were to use this URL for a Piped RSS feed of a Youtube channel:

https://farside.link/pipedapi/feed/unauthenticated/rss?channels=UChIs72whgZI9w6d6FhwGGHA

The template being: https://farside.link/pipedapi/feed/

Farside would choose a Piped instance at random amongst all those without a CDN at that moment and fetch articles from that channel feed from the randomly chosen instance.

(See the list of all Piped instances and their API URLs)

The Piped feeds do not have the same URL structure as Piped videos:

Example video URL from piped.video: https://piped.video/watch?v=GYM9t4c_ev0
Example feed URL from piped.video: https://pipedapi.kavin.rocks/feed/unauthenticated/rss?channels=UChIs72whgZI9w6d6FhwGGHA

This difference in URL structure applies to all Piped instances and is why RSS feeds for Piped do not currently work with Farside.

I would suggest not mixing the Invidious instances with the Piped ones in the pool of instances Farside could pick from with this new Farside pipedapi template as Invidious RSS feeds already work given that Invidious supports Youtube's feed URL structure (https://www.youtube.com/feeds/videos.xml?channel_id=CHANNELID -> https://INVIDIOUS-INSTANCE/feeds/videos.xml?channel_id=CHANNELID).

Thanks