Enemy melee weapon implementation

Description

Added weapon instance to the enemy so the enemy has a weapon it holds. It uses the stats given in the weapon scene. This allows the enemy to deal damage. Current implementation is somewhat limited as seen in the enemy attack script.

Implementation

Set current weapon: This script is used to set the weapon of the enemy in a modular way so different enemies can have different weapons easily. This will allow us to quickly implement different enemies using the already created weapons when implemented completely

@tool
class_name CurrentWeapon
extends Node3D

## Exported Variables
@export_group("weapon")
@export var weapon_scene: PackedScene:
  set(value):
    # Custom setter to validate the scene type
    if value and value.can_instantiate() and value.instantiate() is MeleeWeapon:
      weapon_scene = value
    else:
      push_error("Assigned scene is not a valid Weapon type")
      weapon_scene = null

var current_weapon: MeleeWeapon


func _ready() -> void:
  if not weapon_scene:
    push_error("No valid weapon scene assigned!")
    return

  current_weapon = weapon_scene.instantiate() as MeleeWeapon
  print("set weapon")
  if not current_weapon:
    push_error("Failed to instantiate weapon!")
    return

  add_child(current_weapon)