Add sound effects and character scripts

- Imported new sound effects: "Low Boing", "Low Whoosh", and "Pew" with corresponding import files.
- Created a new character script for "Hen" with basic AI and attack functionality.
- Implemented an effect controller script for managing particle effects with one-shot functionality.

scripts/Statemachine/EffectController.gd

@@ -0,0 +1,17 @@
+extends Node2D
+class_name EffectController
+
+@export var oneShot: bool = true
+
+@onready var particles: GPUParticles2D = $"%particles"
+
+func _ready():
+	particles.emitting = false
+	particles.one_shot = oneShot
+func shot():
+	var cloned = particles.duplicate() as GPUParticles2D
+	cloned.emitting = true
+	add_child(cloned)
+	if oneShot:
+		await cloned.finished
+		cloned.queue_free()