Add backend projects with core models and tests, setup Godot frontend

frontend/scripts/core/Main.cs

@@ -0,0 +1,13 @@
+using Godot;
+
+public partial class Main : Node2D
+{
+    public override void _Ready()
+    {
+        GD.Print("MyBiz - Game Started!");
+    }
+
+    public override void _Process(double delta)
+    {
+    }
+}