feat(task-0005): implement splash delay and loading progress with reactive properties

- Add SplashState delay timer using BootSettings.SplashDurationSeconds with cancellation support
- Implement LoadState progress tracking via ReactiveProperty<float> with step-by-step updates
- Update LoadingUIViewModel to accept and expose Progress reactive property
- Connect LoadingUIView to ViewModel progress changes using UniRx subscriptions
- Add CompositeDisposable for proper cleanup of UI subscriptions in Release()
- Scale ProgressFill transform based on progress value for visual feedback

Выполнена задача TASK-0005 и реализованы splash и loading состояния:
- Добавлен таймер задержки в SplashState с использованием BootSettings.SplashDurationSeconds и поддержкой отмены
- Реализован трекинг прогресса в LoadState через ReactiveProperty<float> со пошаговыми обновлениями
- Обновлён LoadingUIViewModel для принятия и экспорта реактивного свойства Progress
- Подключён LoadingUIView к изменениям прогресса ViewModel с использованием подписок UniRx
- Добавлен CompositeDisposable для правильной очистки UI подписок в Release()
- Масштабирование ProgressFill на основе значения прогресса для визуальной обратной связи

Assets/Scenes/SampleScene.unity

@@ -323,7 +323,8 @@ Transform:
   m_LocalRotation: {x: 0, y: 0, z: 0, w: 1}
   m_LocalPosition: {x: 0, y: 0, z: 0}
   m_LocalScale: {x: 1, y: 1, z: 1}
-  m_Children: []
+  m_Children:
+  - {fileID: 1000000205}
   m_Father: {fileID: 0}
   m_RootOrder: 3
   m_LocalEulerAnglesHint: {x: 0, y: 0, z: 0}
@@ -339,6 +340,37 @@ MonoBehaviour:
   m_Script: {fileID: 11500000, guid: b2222222222222222222222222222222, type: 3}
   m_Name: 
   m_EditorClassIdentifier: 
+  <ProgressFill>k__BackingField: {fileID: 1000000205}
+--- !u!1 &1000000204
+GameObject:
+  m_ObjectHideFlags: 0
+  m_CorrespondingSourceObject: {fileID: 0}
+  m_PrefabInstance: {fileID: 0}
+  m_PrefabAsset: {fileID: 0}
+  serializedVersion: 6
+  m_Component:
+  - component: {fileID: 1000000205}
+  m_Layer: 0
+  m_Name: LoadingProgressFill
+  m_TagString: Untagged
+  m_Icon: {fileID: 0}
+  m_NavMeshLayer: 0
+  m_StaticEditorFlags: 0
+  m_IsActive: 1
+--- !u!4 &1000000205
+Transform:
+  m_ObjectHideFlags: 0
+  m_CorrespondingSourceObject: {fileID: 0}
+  m_PrefabInstance: {fileID: 0}
+  m_PrefabAsset: {fileID: 0}
+  m_GameObject: {fileID: 1000000204}
+  m_LocalRotation: {x: 0, y: 0, z: 0, w: 1}
+  m_LocalPosition: {x: 0, y: 0, z: 0}
+  m_LocalScale: {x: 0, y: 1, z: 1}
+  m_Children: []
+  m_Father: {fileID: 1000000202}
+  m_RootOrder: 0
+  m_LocalEulerAnglesHint: {x: 0, y: 0, z: 0}
 --- !u!1 &1000000301
 GameObject:
   m_ObjectHideFlags: 0

Assets/Scripts/Boot/States/LoadState.cs

@@ -1,24 +1,49 @@
+using System;
 using System.Threading;
 using Cysharp.Threading.Tasks;
+using QuizPleaseTest.Boot.Settings;
 using QuizPleaseTest.Boot.UI;
 using QuizPleaseTest.Common.StateMachine;
+using UniRx;
 
 namespace QuizPleaseTest.Boot.States
 {
     public class LoadState : IState
     {
         private readonly LoadingUIView _view;
+        private readonly BootSettings _settings;
+        private readonly ReactiveProperty<float> _progress = new ReactiveProperty<float>(0f);
 
-        public LoadState(LoadingUIView view)
+        public IReadOnlyReactiveProperty<float> Progress => _progress;
+
+        public LoadState(LoadingUIView view, BootSettings settings)
         {
             _view = view;
+            _settings = settings;
         }
 
-        public UniTask EnterAsync(CancellationToken ct)
+        public async UniTask EnterAsync(CancellationToken ct)
         {
-            _view.Bind(new LoadingUIViewModel());
+            _progress.Value = 0f;
+            _view.Bind(new LoadingUIViewModel(Progress));
             _view.Initialize();
-            return UniTask.CompletedTask;
+
+            int loadSteps = _settings.LoadSteps > 0 ? _settings.LoadSteps : 1;
+            int stepDurationMs = _settings.LoadStepDurationMs > 0 ? _settings.LoadStepDurationMs : 0;
+
+            try
+            {
+                for (int step = 1; step <= loadSteps; step++)
+                {
+                    await UniTask.Delay(stepDurationMs, cancellationToken: ct);
+                    _progress.Value = (float)step / loadSteps;
+                }
+            }
+            catch (OperationCanceledException) when (ct.IsCancellationRequested)
+            {
+                _view.Release();
+                throw;
+            }
         }
 
         public UniTask ExitAsync(CancellationToken ct)

Assets/Scripts/Boot/States/SplashState.cs

@@ -1,24 +1,39 @@
+using System;
 using System.Threading;
 using Cysharp.Threading.Tasks;
+using QuizPleaseTest.Boot.Settings;
 using QuizPleaseTest.Boot.UI;
 using QuizPleaseTest.Common.StateMachine;
+using UnityEngine;
 
 namespace QuizPleaseTest.Boot.States
 {
     public class SplashState : IState
     {
         private readonly SplashUIView _view;
+        private readonly BootSettings _settings;
 
-        public SplashState(SplashUIView view)
+        public SplashState(SplashUIView view, BootSettings settings)
         {
             _view = view;
+            _settings = settings;
         }
 
-        public UniTask EnterAsync(CancellationToken ct)
+        public async UniTask EnterAsync(CancellationToken ct)
         {
             _view.Bind(new SplashUIViewModel());
             _view.Initialize();
-            return UniTask.CompletedTask;
+
+            int delayMs = Mathf.Max(0, Mathf.RoundToInt(_settings.SplashDurationSeconds * 1000f));
+            try
+            {
+                await UniTask.Delay(delayMs, cancellationToken: ct);
+            }
+            catch (OperationCanceledException) when (ct.IsCancellationRequested)
+            {
+                _view.Release();
+                throw;
+            }
         }
 
         public UniTask ExitAsync(CancellationToken ct)

Assets/Scripts/Boot/UI/LoadingUIView.cs

@@ -1,8 +1,45 @@
 using QuizPleaseTest.Common.UI;
+using UniRx;
+using UnityEngine;
 
 namespace QuizPleaseTest.Boot.UI
 {
     public class LoadingUIView : UIView<LoadingUIViewModel>
     {
+        [field: SerializeField] public Transform ProgressFill { get; private set; }
+
+        private CompositeDisposable _disposables;
+
+        public override void Initialize()
+        {
+            base.Initialize();
+
+            _disposables?.Dispose();
+            _disposables = new CompositeDisposable();
+
+            SetProgress(ViewModel.Progress.Value);
+            ViewModel.Progress
+                .Subscribe(SetProgress)
+                .AddTo(_disposables);
+        }
+
+        public override void Release()
+        {
+            _disposables?.Dispose();
+            _disposables = null;
+            base.Release();
+        }
+
+        private void SetProgress(float progress)
+        {
+            if (ProgressFill == null)
+            {
+                return;
+            }
+
+            Vector3 scale = ProgressFill.localScale;
+            scale.x = Mathf.Clamp01(progress);
+            ProgressFill.localScale = scale;
+        }
     }
 }

Assets/Scripts/Boot/UI/LoadingUIViewModel.cs

@@ -1,8 +1,16 @@
+using System;
 using QuizPleaseTest.Common.UI;
+using UniRx;
 
 namespace QuizPleaseTest.Boot.UI
 {
     public class LoadingUIViewModel : IUIViewModel
     {
+        public IReadOnlyReactiveProperty<float> Progress { get; }
+
+        public LoadingUIViewModel(IReadOnlyReactiveProperty<float> progress)
+        {
+            Progress = progress ?? throw new ArgumentNullException(nameof(progress));
+        }
     }
 }