Add Adventure support for chat color arguments

[JorelAli]

Description

The CommandAPI should offer an AdventureChatColorArgument to return NamedTextColor objects instead of ChatColor

Expected code

NamedTextColor color = arguments.get(...)

Extra details

From this Discord discussion: https://discord.com/channels/745416925924032523/745757702608912556/1125919177094471730

[JorelAli]

Feature has been implemented on dev/dev. You can now use the AdventureChatColorArgument to get a NamedTextColor object representing the chat colour provided to you. Because Minecraft's colours support the base 16 colours and reset, but Adventure doesn't have a "colour" for reset, we treat reset as white.

Documentation is still required.

[JorelAli]

Implemented for the next release.

[JorelAli]

Implemented in 9.1.0.