Add oauth support for audio cog

[AndryS0]

What component of Red (cog, command, API) would you like to see improvements on?

Audio

Describe the enhancement you're suggesting.

Right now, the only way to set up YouTube OAuth is to switch to an unmanaged node. However, this could be added as a feature in the Audio cog.

Here’s how I see it:
!llset config oauth // Toggles OAuth login
When enabled, the managed node is stopped and restarted with updated application.yml parameters, setting oauth.enabled: true.
Lavalink outputs an OAuth link and code to stdout, which can be parsed and sent to the owner's DMs.
After logging in, the refresh token must be extracted (from stdout), saved, and used to update application.yml. When !llset config oauth is toggled off, the refresh token is reset, requiring the OAuth setup process to be repeated.

Anything else?

No response

[Dav-Git]

While I can understand the thinking behind this request, I think adding this as a first party feature might not be the best idea.

Using lavalink with OAuth entails a very real risk of account termination. I feel that in this case making the setup a little more involved is a reasonable way to ensure that people enabling this feature know what they are doing.

[AndryS0]

Making something cumbersome is indeed a way to force "think about what are you doing", but for most people facing "video unavailable" issue this is the only way. I think if you add first-time warning written in uppercase telling "DO NOT USE IMPORTANT ACCOUNT" or something similar is enough to both: warn user and make it more convenient.