feat(save): 迁移存读档入口到槽位系统

将游戏流程接入 P2 槽位层：
- SaveRestoreOrchestrator：SaveToAutoSlot / CreateManualSlot / RestoreFromSlot
- GameManager：<<auto_save>> 调用新入口，新增 StartWithSlot 读档入口

保留 RestoreFromFile 旧档兼容路径。

Assets/Scripts/Game Loop/GameManager.cs

@@ -37,7 +37,7 @@ namespace AibisDream
         {
             // 管理游戏开始时各部分的初始化
             SettingLoader.Init();
-            SnapshotBootstrap.EnsureInitialized();
+            SnapshotRegistry.EnsureInitialized();
             // 场景So事件注册
             _currentTalkSceneSo = new BindProperty<TalkSceneSO>();
 
@@ -114,11 +114,24 @@ namespace AibisDream
             StartCoroutine(LoadFromSaveFile(fileName));
         }
 
+        public void StartWithSlot(int slotIndex)
+        {
+            // 游戏开始
+            EnumEventSystem.Global.Send(GameLoopEnum.GameStart);
+
+            StartCoroutine(LoadFromSlot(slotIndex));
+        }
+
         private IEnumerator LoadFromSaveFile(string fileName)
         {
             yield return SaveRestoreOrchestrator.RestoreFromFile(fileName);
         }
 
+        private IEnumerator LoadFromSlot(int slotIndex)
+        {
+            yield return SaveRestoreOrchestrator.RestoreFromSlot(slotIndex);
+        }
+
         private IEnumerator LoadFirstScene()
         {
             ChapterController.Instance.UnlockChapter(_currentTalkSceneSo.Value);
@@ -348,7 +361,7 @@ namespace AibisDream
         [YarnCommand("auto_save")]
         public static void AutoSave()
         {
-            SaveRestoreOrchestrator.SaveToTestPath();
+            SaveRestoreOrchestrator.SaveToAutoSlot();
         }
     }
 

Assets/Scripts/SaveSystem/SaveRestoreOrchestrator.cs

@@ -1,4 +1,4 @@
-using System.Collections;
+using System.Collections;
 using System.Collections.Generic;
 using AibisDream.Framework;
 using AibisDream.Kit;
@@ -9,16 +9,18 @@ using UnityEngine;
 namespace AibisDream.SaveSystem
 {
     /// <summary>
-    /// 存读档流程编排层：连接 UI、<see cref="SnapshotService"/> 与 <see cref="SnapshotPersistence"/>。
+    /// 存读档流程编排层：连接 UI、<see cref="SnapshotService"/> 与槽位系统。
     /// <para>
-    /// 对外入口：<see cref="SaveToTestPath"/>（<<auto_save>>）、<see cref="RestoreFromFile"/>（读档）。
-    /// P4 在此扩展淡入淡出与完整时序；P2 将替换测试路径为槽位 API。
+    /// 对外入口：<see cref="SaveToAutoSlot"/>（&lt;&lt;auto_save&gt;&gt;）、
+    /// <see cref="CreateManualSlot"/>（手动存档）、
+    /// <see cref="RestoreFromSlot"/>（读档）、
+    /// <see cref="RestoreFromFile"/>（旧档/调试）。
     /// </para>
     /// </summary>
     public static class SaveRestoreOrchestrator
     {
-        /// <summary>捕获快照并写入 P1 测试路径；含保存 Loading UI。</summary>
-        public static void SaveToTestPath()
+        /// <summary>捕获快照并写入自动档（slot 0）；含保存 Loading UI。</summary>
+        public static void SaveToAutoSlot()
         {
             var host = YarnVariableStorage.Instance;
             if (host == null)
@@ -36,10 +38,30 @@ namespace AibisDream.SaveSystem
             using (new CodeTimer("SaveSnapshot"))
             {
                 var snapshot = SnapshotService.Capture();
-                SnapshotPersistence.Save(snapshot, SnapshotPersistence.GetTestFilePath());
+                var thumbnail = SlotThumbnailCapture.CapturePng();
+                SlotManager.SaveToAutoSlot(snapshot, thumbnail);
             }
         }
 
+        /// <summary>将当前自动档复制到指定手动档。</summary>
+        public static void CreateManualSlot(int slotIndex)
+        {
+            SlotManager.CopyAutoToManual(slotIndex);
+        }
+
+        /// <summary>从指定槽位读档并还原。</summary>
+        public static IEnumerator RestoreFromSlot(int slotIndex)
+        {
+            var snapshot = SlotManager.LoadSnapshot(slotIndex);
+            if (snapshot == null)
+            {
+                Debug.LogError($"[SaveRestoreOrchestrator] 槽位 {slotIndex} 不存在或读取失败");
+                yield break;
+            }
+
+            yield return RestoreSnapshot(snapshot);
+        }
+
         /// <summary>从文件读档并还原；自动区分新快照格式与 legacy 格式。</summary>
         public static IEnumerator RestoreFromFile(string savePath)
         {
@@ -56,7 +78,7 @@ namespace AibisDream.SaveSystem
                 snapshot = SnapshotPersistence.Load(savePath);
             }
 
-            yield return SnapshotService.Restore(snapshot);
+            yield return RestoreSnapshot(snapshot);
         }
 
         /// <summary>旧档：Yarn 变量 + DeepRepairDataRegistry systemData。</summary>
@@ -72,6 +94,15 @@ namespace AibisDream.SaveSystem
             {
                 yield return DeepRepairDataRegistry.LoadByJson(systemDataJson);
             }
+
+            // 旧档还原后自动固化为新格式，方便后续使用槽位系统
+            var snapshot = SnapshotService.Capture();
+            SlotManager.SaveToAutoSlot(snapshot, null);
+        }
+
+        private static IEnumerator RestoreSnapshot(SaveSnapshot snapshot)
+        {
+            yield return SnapshotService.Restore(snapshot);
         }
     }
 }