feat: add persistence to the opened chest via SceneManager opened_chests array;

Scenes/SceneManager/scene_manager.gd

@@ -1,12 +1,4 @@
 extends Node2D
 
 var player_next_scene_spawn_pos: Vector2
-
-# Called when the node enters the scene tree for the first time.
-func _ready() -> void:
-	pass # Replace with function body.
-
-
-# Called every frame. 'delta' is the elapsed time since the previous frame.
-func _process(delta: float) -> void:
-	pass
+var opened_chests: Array[String] = []