[Dev]: User and org account support

[TylerBloom]

Unmet Need:

Users should be able to interact with their Squire account via SB, even if that's something as simple as keeping a user's account cached and using that to register for tournaments. SquireCore should be able to authenticate users that want to link their accounts.

Similarly, TOs will want to associate their organization's Squire account with their server. This will allow for any new tournaments created in that server to be automatically linked to their org account with the goal of providing identical behavior to what the frontend webserver does.