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

frontend/scripts/ui/GameUI.cs

@@ -0,0 +1,35 @@
+using Godot;
+
+/// <summary>
+/// Базовый класс для всех UI элементов
+/// </summary>
+public partial class GameUI : Control
+{
+    protected GameManager GameManager => GameManager.Instance;
+    
+    public override void _Ready()
+    {
+        ConnectSignals();
+    }
+    
+    protected virtual void ConnectSignals()
+    {
+        if (GameManager != null)
+        {
+            GameManager.MoneyChanged += OnMoneyChanged;
+            GameManager.DateChanged += OnDateChanged;
+        }
+    }
+    
+    protected virtual void OnMoneyChanged(decimal newAmount) { }
+    protected virtual void OnDateChanged(int year, int month, int day) { }
+    
+    public override void _ExitTree()
+    {
+        if (GameManager != null)
+        {
+            GameManager.MoneyChanged -= OnMoneyChanged;
+            GameManager.DateChanged -= OnDateChanged;
+        }
+    }
+}