Bot interaction: copy world changes from one world to another

Allow a player to copy any changes to a world (e.g. item priorities #12 (closed), thresholds #29 (closed)) to another world they are registered to. Do not copy item counts received.

Returns:

• Error message if the player's world context is not set or the destination world is not registered to them
• Success message (or affirmative reaction) when the world data has been copied

Possible command syntax: !item-copy "destination world"