refactor (#6)

Reviewed-on: #6

scripts/Events/CoinStateHandler.cs

@@ -0,0 +1,29 @@
+using Godot;
+using Mr.BrickAdventures.Autoloads;
+
+namespace Mr.BrickAdventures.scripts.Events;
+
+/// <summary>
+/// Handles coin collection events and updates the GameStateStore.
+/// Replaces the manual coin logic in GameManager.
+/// </summary>
+public partial class CoinStateHandler : Node
+{
+    public override void _Ready()
+    {
+        EventBus.Instance.CoinCollected += OnCoinCollected;
+    }
+
+    public override void _ExitTree()
+    {
+        if (EventBus.Instance != null)
+        {
+            EventBus.Instance.CoinCollected -= OnCoinCollected;
+        }
+    }
+
+    private void OnCoinCollected(int amount, Vector2 position)
+    {
+        GameStateStore.Instance?.AddSessionCoins(amount);
+    }
+}