Replace code based linking with microsoft account registration

[odiffey]

As a user I would like to be able to register with my microsoft account, which owns minecraft java or bedrock, and be considered linked upon successful registration.

Microsoft authentication and fetching of minecraft uuid/xuid and player name will need to be added, and the current linking system replaced to consider any microsoft-linked account as linked. If a user does not own the game registration and thus linking will be cancelled.

Need to investigate potential for user uuid/xuid changes, and add handling for player name changes. There is potential a microsoft account could not own the game after initial registration.

https://wiki.vg/Microsoft_Authentication_Scheme