add gamestate, doc and fix

core/photo_mode/collectible_gallery.gd

@@ -0,0 +1,33 @@
+extends Control
+
+@onready var grid_container: GridContainer = $%CollectibleGrid
+@onready var collectible_ui_scene = preload("res://core/photo_mode/collectible_ui.tscn")
+
+func _ready() -> void:
+	CollectionManager.on_collectible_unlocked.connect(_unlock_collectible)
+	setup()
+
+func setup() -> void:
+	var unlocked_collectible_ids = CollectionManager.get_unlocked_collectible_ids()
+	var collectibles = CollectionManager.get_all_collectibles()
+	
+	for child in grid_container.get_children():
+		child.queue_free()
+		
+	for collectible in collectibles:
+		_add_collectible(collectible)
+		if unlocked_collectible_ids.has(collectible.id):
+			_unlock_collectible(collectible.id)
+
+func on_collectible_unlocked(collectible_id: String) -> void:
+	_unlock_collectible(collectible_id)
+
+func _add_collectible(collectible: CollectibleResource) -> void:
+		var collectible_ui: CollectibleUI = collectible_ui_scene.instantiate()
+		collectible_ui.setup(collectible)
+		grid_container.add_child(collectible_ui)
+
+func _unlock_collectible(collectible_id: String) -> void:
+	for collectible_ui in grid_container.get_children():
+		if collectible_ui.collectible_resource.id == collectible_id:
+			collectible_ui.unlock()