Fixed

• With prefix-source: luckperms the name tag above the player still showed the prefix from the prefixes list. The name tag teams were built from that list only, so the LuckPerms prefix never reached them. They are now built from the prefixes LuckPerms returns for the players online.
• With prefix-source: luckperms, players whose LuckPerms group is missing from the prefixes list got the prefix of the last entry in that list. They now get their LuckPerms prefix as well; the list only decides colour and order for them, and they sort below the listed groups.
• Right after joining, before the rank was loaded, a player briefly showed the last entry of the prefixes list.

Tested on Paper 26.3 with LuckPerms on MariaDB. Not tested on Folia or Spigot.