feat(YouTube): Import & Export of subscriptions compatible with newpipe or libretube

[Simpath]

Application

Youtube

Issue

This will provide a way to import export youtube subscription

Patch

It should be able to import newpipe or libretube subscription & export it's subscription that will work on newpipe or libretube

Motivation

Until this date no way (there might be a few I don't know) to import subscription on youtube. Although there is one to export but that is not very convenient and also there's no point if you can't import it back.

Acknowledgements

• I have searched the existing issues and this is a new and no duplicate or related to another open issue.
• I have written a short but informative title.
• I filled out all of the requested information in this issue properly.

[SodaWithoutSparkles]

Work has to be done on google's side. Not RV

[venkat2305]

I think it's possible to get the list of all our subscriptions from the revanced app itself

[SodaWithoutSparkles]

but it youtube doesn't allow importing subscriptions, does it?

Therefore, as I said, work has to be done on Google's side, not ReVanced. You can already export YouTube subscriptions to newpipe. I think I have done it before.

[LisoUseInAIKyrios]

Exporting subscriptions would need to be a separate app or service. The subscriptions are not stored locally on the YT app (at least, there is no database or anything local that can be queried)