server: add a private socket for root

server: add a private socket for root

root will try and use it if possible; anything connecting on it
is allowed through without knowing a password.

The jukebox user will be able to use it too although it doesn't
actually try.

Both these users have RW access to the database so they aren't
being given any privilege they don't have already here.

The speaker socket moves to the same private directory.