Ninja garb should hide player name

[Arcanorum]

Task description

Currently the ninja garb armour doesn't actual hide the display name of a player wearing it like it's item description says.

This item is intended to allow players to maintain anonymity so they can attempt surprise attacks/assassinations on other players without fear of repercussion later when they aren't wearing it.

References/notes

This should be done on the server side to avoid players being able to manually show the display name for a player entity on the client.
Where player display name is retrieved from the player entity: https://github.com/Arcanorum/dungeonz/blob/master/server/src/entities/classes/destroyables/movables/characters/Player.js#L200
Similar name change functionality (add this to the ninja garb item for when it is equipped/unequipped): https://github.com/Arcanorum/dungeonz/blob/master/server/src/entities/classes/destroyables/movables/characters/Player.js#L505

Acceptance criteria

• When a ninja garb is equipped, that player's display name should be shown as "???" to all players in range.
• When a player with a ninja garb equipped comes into view of a player, their display name should be shown as "???".
• When a player wearing a ninja garb unequips it, their display name should be set to their true display name for all players in range.
• When a player wearing a ninja garb sends a chat message, the name of the player in the chat box should be shown as "???".

[mtrunt]

I'd like to give this a shot.

[Arcanorum]

Sure