Fix chat formatting on Cardboard servers

[slyphmp4]

Что исправлено

Cardboard exposes Paper's AsyncChatEvent class for API compatibility, but its chat pipeline may continue to dispatch the legacy Bukkit AsyncPlayerChatEvent. CloverChat previously treated mere class availability as proof that AsyncChatEvent was usable and therefore skipped registration of the legacy listener entirely.

This caused CloverChat commands to work while normal player chat bypassed CloverChat formatting on Cardboard.

Изменения

• Detect Cardboard from the Bukkit server name/version fingerprint.
• On Cardboard, skip ModernChatBridge and register the existing ChatListener using AsyncPlayerChatEvent.
• Keep the existing AsyncChatEvent behavior unchanged on Paper/Purpur-compatible servers.
• Report AsyncPlayerChatEvent (Cardboard compatibility) in the startup banner.

Scope

Only CloverChatPlugin.java is changed. No chat formatting, permissions, proxy sync, or message dispatch logic was modified.