Implement MVP for the statue decoration minigame (#65)

MVP implemented with:
- placing, removing etc. decorations
- saving the state, displaying it on the map, restoring when game restarts
- saving screenshots to folder on device

Co-authored-by: Michal Pikulski <michal@foolhardyhorizons.com>
Co-authored-by: Michal Pikulski <michal.a.pikulski@gmail.com>
Reviewed-on: #65

Assets/Scripts/Minigames/StatueDressup/IReadyNotifier.cs

@@ -0,0 +1,63 @@
+using System;
+
+namespace Minigames.StatueDressup
+{
+    /// <summary>
+    /// Interface for managers that load asynchronously and notify when ready.
+    /// Allows dependent components to safely access the manager via WhenReady callbacks.
+    /// </summary>
+    public interface IReadyNotifier
+    {
+        /// <summary>
+        /// True when the manager has finished initialization and is ready to use
+        /// </summary>
+        bool IsReady { get; }
+        
+        /// <summary>
+        /// Event invoked when the manager becomes ready
+        /// </summary>
+        event Action OnReady;
+    }
+    
+    /// <summary>
+    /// Extension methods for IReadyNotifier to provide common callback behavior
+    /// </summary>
+    public static class ReadyNotifierExtensions
+    {
+        /// <summary>
+        /// Execute callback when ready. If already ready, executes immediately.
+        /// If not ready yet, subscribes to OnReady event and executes when fired.
+        /// </summary>
+        public static void WhenReady(this IReadyNotifier notifier, Action callback)
+        {
+            if (notifier == null)
+            {
+                Core.Logging.Warning("[ReadyNotifierExtensions] Notifier is null, cannot execute callback");
+                return;
+            }
+            
+            if (callback == null)
+            {
+                return;
+            }
+            
+            if (notifier.IsReady)
+            {
+                // Already ready - execute immediately
+                callback.Invoke();
+            }
+            else
+            {
+                // Not ready yet - subscribe to event and auto-unsubscribe after invocation
+                Action handler = null;
+                handler = () =>
+                {
+                    callback.Invoke();
+                    notifier.OnReady -= handler; // Unsubscribe to prevent memory leaks
+                };
+                notifier.OnReady += handler;
+            }
+        }
+    }
+}
+