Feature: Add friends checkbox to separate local state, for IsOnFriendsList param

[Jashepp]

This adds a friends checkbox to separate local state, to allow the new IsOnFriendsList VRChat parameter to be used.

Related issue: #182

I did think of other ways of doing this, like having a new option instead of combining it with local state, or also renaming the 'In local' and 'In remote' text when it's checked, but a lot more would have to be changed to do either. This PR can turn into that, or it can be done later with this small implementation for now instead?

I have tested this manually and when checked/on, it works as expected. I also looked at the built animation controller and it looks good in there too. Tested for myself, for friends, and when unfriending they see it change to the remote state automatically, same when befriending someone, they see it change to the 'local' state.

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