Shroud per team

[anvilvapre]

Relates to #21403.

Each player has a shroud instance. On each actor move the shroud of all players is updated.

In larger multiple player games there are often only 2-4 teams. The more players, the more likely there are teams.

Proposal to main one Shroud per team and one for spectators.

Implementation should be fairly straight forward. Rather than iterating all shrouds of each player we iterate all unique shrouds in across players. Shroud may need a reference counter to mark if still in use by a player.

A player mask may be needed to indicate unique items per player. Although i believe currently teams shrouds are literally identical for each player in the teams.

Would benefit multiplayer team games.