feat: more plugin work and intra-scope communication

Game/CurrentLevel.cs

@@ -0,0 +1,13 @@
+using GodotHostTest.Interfaces;
+
+namespace GodotHostTest.Game;
+
+public class CurrentLevel : ICurrentLevel
+{
+    public int LevelNumber { get; private set; } = 1;
+
+    public void NextLevel()
+    {
+        LevelNumber++;
+    }
+}