fix(auth): accept equivalencies when comparing scopes

[iProdigy]

Type: Bugfix

Fixes #342
Fixes #323
Closes #335

• Changes compareScopes from an O(n*m) operation to O(n+m)
• Accept kraken/helix scope equivalencies for compareScopes
• Accept user:edit:broadcast for channel:manage:broadcast in compareScopes
• channel_subscriptions => channel:read:subscriptions for channel-subscribe-events-v1
• user:edit:broadcast => channel:manage:broadcast for updateChannelInfo, createStreamMarker, and replaceStreamTags

[theca11]

Could this be used to fix #323 too? (user:edit:broadcast -> channel:manage:broadcast)

[iProdigy]

Could this be used to fix #323 too? (user:edit:broadcast -> channel:manage:broadcast)

Yes, but extra care would be needed to not accept the reverse (for example in helix Update User Extensions) -- that said, the library doesn't appear to currently implement this endpoint so it may be a non-issue

Edit: depending on what scope validation the chat package does, the reverse mappings could be eliminated

Edit2: looks like there's already a legacyScopes flag for the chat package, so a helix => legacy mapping doesn't seem to be necessary

[d-fischer]

Could this be used to fix #323 too? (user:edit:broadcast -> channel:manage:broadcast)

Yes, this fixes #323 and supersedes #335 now. I think this is much more elegant and accomplishes the same without ever requiring a breaking change.

[d-fischer]

Edit: depending on what scope validation the chat package does, the reverse mappings could be eliminated

Edit2: looks like there's already a legacyScopes flag for the chat package, so a helix => legacy mapping doesn't seem to be necessary

Indeed, chat has to do a very strict validation here, since the required scope depends entirely on when the application was created on the Twitch dev portal. From my tests back when the change was introduced, "new" apps don't support the "old" scopes and vice versa.