feat: integrate composable Godot runtime and EventBus debugger

Godot/Samples/ShrinkSDK.Godot.Sample/WorldDemoWorld.cs

@@ -0,0 +1,62 @@
+#nullable enable
+using System;
+using Godot;
+using ShrinkEventBus;
+
+public partial class WorldDemoWorld : Node
+{
+    private IDisposable? _binding;
+    private bool _restoring = true;
+    private readonly DemoWorldSubscriber _subscriber = new();
+    public ShrinkBusKey Key { get; } = ShrinkBusKey.World(Guid.NewGuid().ToString("N"));
+    public IShrinkEventBus Bus { get; private set; } = null!;
+    public int ReadyCount => _subscriber.ReadyCount;
+    public int EffectCount => _subscriber.EffectCount;
+
+    public override void _EnterTree()
+    {
+        Bus = EventBus.CreateBus(Key, new ShrinkBusOptions
+        {
+            Scheduler = ShrinkBusSchedulerKind.MainThread,
+            DispatchMode = ShrinkDispatchMode.Ordered,
+            QueueCapacity = 32
+        });
+        _binding = EventBus.Attach(_subscriber, Key);
+    }
+
+    public void Restore(bool fail)
+    {
+        Post(new DemoEffect());
+        if (fail) throw new InvalidOperationException("Candidate restore failed.");
+    }
+
+    public void Commit()
+    {
+        _restoring = false;
+        Post(new DemoWorldReady());
+    }
+
+    private void Post<T>(T value) where T : IShrinkEvent
+    {
+        if (!_restoring) Bus.Post(value);
+    }
+
+    public override void _ExitTree()
+    {
+        _binding?.Dispose();
+        _binding = null;
+        EventBus.RemoveBus(Key);
+    }
+}
+
+public readonly struct DemoWorldReady : IShrinkEvent { }
+public readonly struct DemoEffect : IShrinkEvent { }
+
+[ShrinkEventSubscriber]
+public sealed class DemoWorldSubscriber
+{
+    public int ReadyCount { get; private set; }
+    public int EffectCount { get; private set; }
+    [ShrinkSubscribe] private void OnReady(DemoWorldReady value) => ReadyCount++;
+    [ShrinkSubscribe] private void OnEffect(DemoEffect value) => EffectCount++;
+}