feat(task-0006): implement menu restart button and signal coordination

- Update MenuUIViewModel with IMenuRestartSignal dependency and Restart() method
- Add RestartButton to MenuUIView with listener management in Initialize/Release
- Connect MenuUIView click handler to ViewModel.Restart() callback
- Fix race condition in MenuRestartSignal.RequestRestart() by nulling completion source first
- Wrap MenuState.WaitAsync() in try-catch for proper view cleanup on cancellation
- Update TASK-0006 status to Ready

Выполнена задача TASK-0006: реализована кнопка Restart и координация сигналов

- Обновлён MenuUIViewModel с зависимостью IMenuRestartSignal и методом Restart()
- Добавлена кнопка RestartButton в MenuUIView с управлением слушателями в Initialize/Release
- Подключен обработчик кликов MenuUIView к колбэку ViewModel.Restart()
- Исправлено состояние гонки в MenuRestartSignal.RequestRestart() путем обнуления completion source
- Обёрнут WaitAsync в MenuState в try-catch для корректной очистки view при отмене
- Обновлён статус TASK-0006 до Ready

Agent/Task/TASK-0006.md

@@ -1,5 +1,9 @@
 # TASK-0006: MenuState и Restart
 
+## Статус
+
+Ready
+
 ## Цель
 
 Реализовать меню с кнопкой `Restart`, которое завершает `MenuState` и возвращает flow к загрузке.

Assets/Scenes/SampleScene.unity

@@ -381,6 +381,7 @@ GameObject:
   m_Component:
   - component: {fileID: 1000000302}
   - component: {fileID: 1000000303}
+  - component: {fileID: 1000000304}
   m_Layer: 0
   m_Name: MenuView
   m_TagString: Untagged
@@ -414,3 +415,48 @@ MonoBehaviour:
   m_Script: {fileID: 11500000, guid: b3333333333333333333333333333333, type: 3}
   m_Name: 
   m_EditorClassIdentifier: 
+  <RestartButton>k__BackingField: {fileID: 1000000304}
+--- !u!114 &1000000304
+MonoBehaviour:
+  m_ObjectHideFlags: 0
+  m_CorrespondingSourceObject: {fileID: 0}
+  m_PrefabInstance: {fileID: 0}
+  m_PrefabAsset: {fileID: 0}
+  m_GameObject: {fileID: 1000000301}
+  m_Enabled: 1
+  m_EditorHideFlags: 0
+  m_Script: {fileID: 11500000, guid: 4e29b1a8efbd4b44bb3f3716e73f07ff, type: 3}
+  m_Name: 
+  m_EditorClassIdentifier: 
+  m_Navigation:
+    m_Mode: 3
+    m_WrapAround: 0
+    m_SelectOnUp: {fileID: 0}
+    m_SelectOnDown: {fileID: 0}
+    m_SelectOnLeft: {fileID: 0}
+    m_SelectOnRight: {fileID: 0}
+  m_Transition: 1
+  m_Colors:
+    m_NormalColor: {r: 1, g: 1, b: 1, a: 1}
+    m_HighlightedColor: {r: 0.88235295, g: 0.88235295, b: 0.88235295, a: 1}
+    m_PressedColor: {r: 0.69803923, g: 0.69803923, b: 0.69803923, a: 1}
+    m_SelectedColor: {r: 0.88235295, g: 0.88235295, b: 0.88235295, a: 1}
+    m_DisabledColor: {r: 0.52156866, g: 0.52156866, b: 0.52156866, a: 0.5019608}
+    m_ColorMultiplier: 1
+    m_FadeDuration: 0.1
+  m_SpriteState:
+    m_HighlightedSprite: {fileID: 0}
+    m_PressedSprite: {fileID: 0}
+    m_SelectedSprite: {fileID: 0}
+    m_DisabledSprite: {fileID: 0}
+  m_AnimationTriggers:
+    m_NormalTrigger: Normal
+    m_HighlightedTrigger: Highlighted
+    m_PressedTrigger: Pressed
+    m_SelectedTrigger: Selected
+    m_DisabledTrigger: Disabled
+  m_Interactable: 1
+  m_TargetGraphic: {fileID: 0}
+  m_OnClick:
+    m_PersistentCalls:
+      m_Calls: []

Assets/Scripts/Boot/Flow/MenuRestartSignal.cs

@@ -17,7 +17,9 @@ namespace QuizPleaseTest.Boot.Flow
 
         public void RequestRestart()
         {
-            _restartCompletionSource?.TrySetResult();
+            UniTaskCompletionSource restartCompletionSource = _restartCompletionSource;
+            _restartCompletionSource = null;
+            restartCompletionSource?.TrySetResult();
         }
     }
 }

Assets/Scripts/Boot/States/MenuState.cs

@@ -1,3 +1,4 @@
+using System;
 using System.Threading;
 using Cysharp.Threading.Tasks;
 using QuizPleaseTest.Boot.Flow;
@@ -19,10 +20,19 @@ namespace QuizPleaseTest.Boot.States
 
         public async UniTask EnterAsync(CancellationToken ct)
         {
-            _view.Bind(new MenuUIViewModel());
+            _view.Bind(new MenuUIViewModel(_restartSignal));
             _view.Initialize();
+
+            try
+            {
                 await _restartSignal.WaitAsync(ct);
             }
+            catch (OperationCanceledException) when (ct.IsCancellationRequested)
+            {
+                _view.Release();
+                throw;
+            }
+        }
 
         public UniTask ExitAsync(CancellationToken ct)
         {

Assets/Scripts/Boot/UI/MenuUIView.cs

@@ -1,8 +1,39 @@
 using QuizPleaseTest.Common.UI;
+using UnityEngine;
+using UnityEngine.UI;
 
 namespace QuizPleaseTest.Boot.UI
 {
     public class MenuUIView : UIView<MenuUIViewModel>
     {
+        [field: SerializeField] public Button RestartButton { get; private set; }
+
+        public override void Initialize()
+        {
+            base.Initialize();
+
+            if (RestartButton == null)
+            {
+                return;
+            }
+
+            RestartButton.onClick.RemoveListener(OnRestartClicked);
+            RestartButton.onClick.AddListener(OnRestartClicked);
+        }
+
+        public override void Release()
+        {
+            if (RestartButton != null)
+            {
+                RestartButton.onClick.RemoveListener(OnRestartClicked);
+            }
+
+            base.Release();
+        }
+
+        private void OnRestartClicked()
+        {
+            ViewModel.Restart();
+        }
     }
 }

Assets/Scripts/Boot/UI/MenuUIViewModel.cs

@@ -1,8 +1,21 @@
+using System;
+using QuizPleaseTest.Boot.Flow;
 using QuizPleaseTest.Common.UI;
 
 namespace QuizPleaseTest.Boot.UI
 {
     public class MenuUIViewModel : IUIViewModel
     {
+        private readonly IMenuRestartSignal _restartSignal;
+
+        public MenuUIViewModel(IMenuRestartSignal restartSignal)
+        {
+            _restartSignal = restartSignal ?? throw new ArgumentNullException(nameof(restartSignal));
+        }
+
+        public void Restart()
+        {
+            _restartSignal.RequestRestart();
+        }
     }
 }