* Send message to Java if command is Bedrock-only
If a Java player attempts to use a Bedrock-only command, such as `geyser statistics`, they will get an error message stating that this command is only for Bedrock players.
This commit also cleans up Velocity Adventure dependency usage. Issues were caused because of the way relocation works and because Velocity also uses Adventure.
* Only look for a session if we have to
* Update languages submodule
* Introduce CommandSender.getLocale()
This allows Geyser-specific commands (e.g. `/geyser help`) to be displayed in the (Java or Bedrock) player's default language, which stops those commands from simply being displayed in the default locale.
* Tweak Javadoc
* Set CommandManager's GeyserConnector to final
* Clean up
- Added `GeyserCommand.isExecutableOnConsole()`. If this is set to false, the command will not appear as an option in the GUI.
- Added `GeyserCommand.getSubCommands()`. If not empty, the subcommand options will now appear in the GUI.
* Implement helper methods for sending packets, fixes an NPE when chatting before connecting to the remote server
* Change method names
* Add a space between doc comment lines
* Add debug messages