Make key items (flower and key staff)

Implement fog door for unlockable doors

Zennysoft.Game.Ma/src/items/effect/KeyItemStats.cs

@@ -0,0 +1,11 @@
+using Chickensoft.Introspection;
+using Godot;
+
+namespace Zennysoft.Game.Ma;
+
+[GlobalClass]
+[Meta, Id("key_item_stats")]
+public partial class KeyItemStats : InventoryItemStats
+{
+
+}