Handle follower emotes differently if subscribed

[baines]

If we also have a subscriber emote set for a channel, then don't treat a follower emote set as local to that channel.

Description

On Twitch it's possible to use a channel's follower emotes everywhere if also subscribed to the followed channel.
But Chatterino did not show the emotes as available in other channels or allow them to be auto-completed in this case.

This PR makes a small change so that if we also have a subscriber emote set for a channel, then the follower emote set is not treated as local.

I know there's another PR to implement this behaviour (#4281) but I'm not confident enough with the changes in there to pick that one up.

This code doesn't attempt to convert an existing local set into a non-local one or vice versa (when subscription is gained/lost). I don't know if twitch sends another GLOBALUSERSTATE with the emote sets when that happens or what.

It's also making an assumption that loadUserstateEmotes is called only once after all the emote sets are known. If they can come in "piecemeal" then it might not find the subscriber set if it's in a later batch than the follower one.

(felanbird): Closes #4233

[github-actions]

clang-tidy made some suggestions

[Felanbird]

Those suggestions are all shit you can go ahead and revert them, the bot doesn't always get it right

[iProdigy]

nice work

[iProdigy]

Also, we could hook on subscription event to update local status for the relevant follower emotes (but this can happen in a separate PR)

[Nerixyz]

Seems good. Just a note: Twitch announced a Get User Emotes endpoint in their Standard Output stream. However, it isn't clear how this will handle follower emotes.

[Felanbird]

I'm happy with this change, prevent the double serialization on merge if anyone really cares (they probably do) but I'm glad to have a working solution to this.

[iProdigy]

Great first contribution!

[pajlada]

@Mm2PL want to take a peek?

[Mm2PL]

LGTM, works as expected. Thank you for your contribution.

[pajlada]

Thank you @baines! As a first-time contributor, you can now add yourself to the contributors list that's shown inside the About page in Chatterino.

If you want this, you can open a new PR where you modify the resources/contributors.txt file and add yourself to the list. Make sure to read the comments at the top for instructions.