Enable linking to any player identities you have access to

[sussexrick]

It should be possible for a team owner to link identities between multiple teams within their club.

However, you cannot simply offer identities from their club, because a club owner can add any team, which would mean you could add a player from any team and effectively be a team owner for that team - an elevation of privilege.

Check which teams the current user is an owner for, and offer identities from those. This will frequently be the other teams in the club, but it could also be others that they are responsible for.

Update Players.md when done.