Add Custom Keybind Support for Datapacks

Datapacks should be able to define custom keybinds that players can use to trigger functions. For example, pressing a key like "G" could run a function from the datapack. This would allow smoother, more interactive experiences in custom maps or systems like opening a custom menu, activating an ability, or toggling a feature without using commands or chat. These keybinds could be declared in a JSON file and assigned in the controls menu like regular keys.