Add skill upgrade system and refactor skill components for enhanced functionality; update resource paths and configurations

scripts/Resources/SkillUpgrade.cs

@@ -0,0 +1,12 @@
+using Godot;
+using Godot.Collections;
+
+namespace Mr.BrickAdventures.scripts.Resources;
+
+[GlobalClass]
+public partial class SkillUpgrade : Resource
+{
+    [Export] public int Cost { get; set; } = 50;
+    [Export(PropertyHint.MultilineText)] public string Description { get; set; } = "Upgrade Description";
+    [Export] public Dictionary<string, Variant> Properties { get; set; } = new();
+}