feat(角色): 添加新角色资源及调整现有角色属性

新增狗、猫、鸡、MTY等角色的图片和动画资源，并调整部分角色的属性和动画逻辑。包括：
- 添加狗角色的行走动画和图片资源
- 更新猫角色的行走动画和碰撞体
- 调整鸡角色的属性和动画帧
- 修改MTY角色的攻击冷却时间
- 更新彩虹糖的数值属性
- 优化链式机枪的攻击力属性
- 添加企鹅角色的多帧动画资源
- 更新熊角色的行走动画和面具资源

同时修复了部分角色的碰撞体大小和位置问题。

scripts/Contents/Characters/Cat.gd

@@ -6,6 +6,8 @@ func register():
 	fields[FieldStore.Entity.MOVEMENT_SPEED] = randf_range(0.5, 0.8)
 	attackCooldownMap[0] = randi_range(5000, 8000)
 	sprintMultiplier = randf_range(5, 15)
+func spawn():
+	texture.play("walk")
 func ai():
 	PresetEntityAI.follow(self, currentFocusedBoss)
 	tryAttack(0, true)

scripts/Contents/Characters/Dog.gd

@@ -5,7 +5,8 @@ func register():
 	fields[FieldStore.Entity.MOVEMENT_SPEED] = 0.2
 	fields[FieldStore.Entity.OFFSET_SHOOT] = 0
 	attackCooldownMap[0] = randi_range(3000, 5000)
-
+func spawn():
+	texture.play("walk")
 func ai():
 	PresetEntityAI.follow(self, currentFocusedBoss, 300)
 	tryAttack(0)

scripts/Contents/Characters/Hen.gd

@@ -5,7 +5,8 @@ func register():
 	fields[FieldStore.Entity.MAX_HEALTH] = 100
 	fields[FieldStore.Entity.MOVEMENT_SPEED] = 0.3
 	fields[FieldStore.Entity.OFFSET_SHOOT] = 10
-
+func spawn():
+	texture.play("walk")
 func ai():
 	attackCooldownMap[0] = randi_range(1500, 4000)
 	PresetEntityAI.follow(self, currentFocusedBoss, 300)

scripts/Contents/Characters/MTY.gd

@@ -4,9 +4,11 @@ class_name MTY
 func register():
 	fields[FieldStore.Entity.MAX_HEALTH] = 400
 	fields[FieldStore.Entity.MOVEMENT_SPEED] = 0.9
-	attackCooldownMap[0] = 1500
-	attackCooldownMap[1] = 500
+	attackCooldownMap[0] = 1000
+	attackCooldownMap[1] = 250
 	sprintMultiplier = 5
+func spawn():
+	texture.play("walk")
 func ai():
 	PresetEntityAI.follow(self, currentFocusedBoss)
 	tryAttack(0)