Updated to 1.20.4

• Added an overlay to display the current spell.
• Spells can now have a Pre-Cast that allows the player to select Blocks or Entities before casting.
• Spells can now have defined Catalysts that must be present in the Off-Hand of the player before casting.
• Added Command: clearSpellSlot to reset a spell in all or a specific slot.
• Class Types can specify whether or not to use a custom set of sprites for the Spell Overlay.
• Added an InstantSpell class that has no drawTime.
• Added a Mana "system" utilising player data and the player's current Class Type.
• Added Events that are called when: Blocks or Entities are selected, Mana is healed and when Mana regenerates.
• Reorganised the code for SpellCastingItem's tooltip.
• Added a method in ClientUtil for creating a cube outline with a selected Particle Type.