Adds a new optional `pet-name` property to arena class configurations that lets server owners set a custom pet name template instead of the hardcoded "<player>'s pet". This allows for translation and color coding. To accommodate setups where the player's "display name" isn't a good fit, e.g. because it is too long, the more generic "player name" is available for use instead.
Closes#595
Co-authored-by: Bobcat00 <[email protected]>
Co-authored-by: Andreas Troelsen <[email protected]>
