diff --git a/Assets/Scripts/AssetRefs/ConstRef.cs b/Assets/Scripts/AssetRefs/ConstRef.cs
index b4c2dfb6e..fbca620f5 100644
--- a/Assets/Scripts/AssetRefs/ConstRef.cs
+++ b/Assets/Scripts/AssetRefs/ConstRef.cs
@@ -23,6 +23,16 @@ namespace AibisDream.Utility
 
         public static readonly string SaveFilePath = Path.Combine(Application.persistentDataPath, "AllOurBrokenParts", "saves");
 
+        /// <summary>P2 槽位相关常量。</summary>
+        public const int SaveSlotCount = 8;
+        public const int SaveThumbnailWidth = 640;
+        public const int SaveThumbnailHeight = 360;
+        public const string SaveSlotDirPrefix = "slot_";
+        public const string SaveSnapshotFileName = "snapshot";
+        public const string SaveMetaFileName = "meta";
+        public const string SaveThumbnailFileName = "thumbnail";
+        public const string LatestSlotFileName = "latest_slot";
+
         /// <summary>P1 快照层自测落盘路径（P2 槽位层接管后迁移）。</summary>
         public static readonly string SnapshotTestPath =
             Path.Combine(Application.persistentDataPath, "AllOurBrokenParts", "snapshot_test");
diff --git a/Assets/Scripts/SaveSystem/CloudSave.meta b/Assets/Scripts/SaveSystem/CloudSave.meta
new file mode 100644
index 000000000..308741781
--- /dev/null
+++ b/Assets/Scripts/SaveSystem/CloudSave.meta
@@ -0,0 +1,8 @@
+fileFormatVersion: 2
+guid: 520cc163c88e4c00895fe201004b4384
+folderAsset: yes
+DefaultImporter:
+  externalObjects: {}
+  userData:
+  assetBundleName:
+  assetBundleVariant:
diff --git a/Assets/Scripts/SaveSystem/CloudSave/CloudSaveManager.cs b/Assets/Scripts/SaveSystem/CloudSave/CloudSaveManager.cs
new file mode 100644
index 000000000..d8db81960
--- /dev/null
+++ b/Assets/Scripts/SaveSystem/CloudSave/CloudSaveManager.cs
@@ -0,0 +1,102 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Threading.Tasks;
+using UnityEngine;
+
+namespace AibisDream.SaveSystem.CloudSave
+{
+    /// <summary>
+    /// 云存档协调器：负责选择当前平台的 backend，并在槽位写入/读取后触发同步钩子。
+    /// <para>
+    /// P2 不实现真实云同步逻辑，仅保留扩展点。
+    /// </para>
+    /// </summary>
+    public static class CloudSaveManager
+    {
+        private static readonly List<ICloudSaveBackend> Backends = new();
+
+        /// <summary>注册一个云存档后端。应在游戏启动时调用一次。</summary>
+        public static void RegisterBackend(ICloudSaveBackend backend)
+        {
+            if (backend == null)
+            {
+                return;
+            }
+
+            Backends.Add(backend);
+        }
+
+        /// <summary>清空已注册后端（主要用于测试）。</summary>
+        public static void ClearBackends()
+        {
+            Backends.Clear();
+        }
+
+        /// <summary>槽位写入后调用：触发所有可用后端的异步上传。</summary>
+        public static void OnSlotWritten(int slotIndex)
+        {
+            _ = UploadSlotAsync(slotIndex);
+        }
+
+        /// <summary>槽位读取前调用：可触发下载（P2 默认不自动下载，避免覆盖本地进度）。</summary>
+        public static void OnSlotRestored(int slotIndex)
+        {
+            // P2 占位：未来可在此触发冲突检测与下载。
+        }
+
+        /// <summary>手动触发指定槽位的云同步上传。</summary>
+        public static async Task UploadSlotAsync(int slotIndex)
+        {
+            var filePaths = CollectSlotFilePaths(slotIndex);
+            if (filePaths.Count == 0)
+            {
+                return;
+            }
+
+            foreach (var backend in Backends)
+            {
+                if (!backend.IsAvailable)
+                {
+                    continue;
+                }
+
+                try
+                {
+                    await backend.UploadSlotAsync(slotIndex, filePaths.ToArray());
+                    Debug.Log($"[CloudSaveManager] {backend.PlatformName} 上传槽位 {slotIndex} 完成。");
+                }
+                catch (Exception ex)
+                {
+                    Debug.LogWarning($"[CloudSaveManager] {backend.PlatformName} 上传槽位 {slotIndex} 失败: {ex.Message}");
+                }
+            }
+        }
+
+        /// <summary>收集槽位下需要同步的文件路径。</summary>
+        private static List<string> CollectSlotFilePaths(int slotIndex)
+        {
+            var paths = new List<string>();
+
+            var snapshotPath = SlotDirectory.GetSnapshotPath(slotIndex);
+            if (File.Exists(snapshotPath))
+            {
+                paths.Add(snapshotPath);
+            }
+
+            var metaPath = SlotDirectory.GetMetaPath(slotIndex);
+            if (File.Exists(metaPath))
+            {
+                paths.Add(metaPath);
+            }
+
+            var thumbnailPath = SlotDirectory.GetThumbnailPath(slotIndex);
+            if (File.Exists(thumbnailPath))
+            {
+                paths.Add(thumbnailPath);
+            }
+
+            return paths;
+        }
+    }
+}
diff --git a/Assets/Scripts/SaveSystem/CloudSave/CloudSaveManager.cs.meta b/Assets/Scripts/SaveSystem/CloudSave/CloudSaveManager.cs.meta
new file mode 100644
index 000000000..5d33b3aa0
--- /dev/null
+++ b/Assets/Scripts/SaveSystem/CloudSave/CloudSaveManager.cs.meta
@@ -0,0 +1,11 @@
+fileFormatVersion: 2
+guid: 87e980f299ac4341947c076cff16dc81
+MonoImporter:
+  externalObjects: {}
+  serializedVersion: 2
+  defaultReferences: []
+  executionOrder: 0
+  icon: {instanceID: 0}
+  userData:
+  assetBundleName:
+  assetBundleVariant:
diff --git a/Assets/Scripts/SaveSystem/CloudSave/ICloudSaveBackend.cs b/Assets/Scripts/SaveSystem/CloudSave/ICloudSaveBackend.cs
new file mode 100644
index 000000000..867440ef2
--- /dev/null
+++ b/Assets/Scripts/SaveSystem/CloudSave/ICloudSaveBackend.cs
@@ -0,0 +1,37 @@
+using System;
+using System.Threading.Tasks;
+
+namespace AibisDream.SaveSystem.CloudSave
+{
+    /// <summary>
+    /// 云存档后端适配器接口。
+    /// <para>
+    /// P2 仅定义接口与本地 no-op 实现，未来 Steamworks.NET / TapTap TDS SDK 通过实现此接口接入。
+    /// 每个槽位在本地对应一组文件（snapshot.json / meta.json / thumbnail.png），
+    /// backend 可选择逐文件上传，或将整组文件打包后上传。
+    /// </para>
+    /// </summary>
+    public interface ICloudSaveBackend
+    {
+        /// <summary>平台名称，用于日志。</summary>
+        string PlatformName { get; }
+
+        /// <summary>当前平台是否可用。</summary>
+        bool IsAvailable { get; }
+
+        /// <summary>上传槽位文件集。</summary>
+        /// <param name="slotIndex">槽位编号。</param>
+        /// <param name="filePaths">该槽位下需要同步的文件绝对路径。</param>
+        Task UploadSlotAsync(int slotIndex, string[] filePaths);
+
+        /// <summary>下载槽位文件集到目标目录。</summary>
+        Task DownloadSlotAsync(int slotIndex, string targetDirectory);
+
+        /// <summary>删除云端槽位。</summary>
+        Task DeleteSlotAsync(int slotIndex);
+
+        /// <summary>获取云端该槽位的时间戳，用于冲突检测。</summary>
+        /// <returns>远程保存时间；不存在返回 null。</returns>
+        Task<DateTime?> GetRemoteTimestampAsync(int slotIndex);
+    }
+}
diff --git a/Assets/Scripts/SaveSystem/CloudSave/ICloudSaveBackend.cs.meta b/Assets/Scripts/SaveSystem/CloudSave/ICloudSaveBackend.cs.meta
new file mode 100644
index 000000000..71ddf8481
--- /dev/null
+++ b/Assets/Scripts/SaveSystem/CloudSave/ICloudSaveBackend.cs.meta
@@ -0,0 +1,11 @@
+fileFormatVersion: 2
+guid: 783cf442f0484df9a89c7841604c0b49
+MonoImporter:
+  externalObjects: {}
+  serializedVersion: 2
+  defaultReferences: []
+  executionOrder: 0
+  icon: {instanceID: 0}
+  userData:
+  assetBundleName:
+  assetBundleVariant:
diff --git a/Assets/Scripts/SaveSystem/SlotFileSystem.cs b/Assets/Scripts/SaveSystem/SlotFileSystem.cs
new file mode 100644
index 000000000..4083eb4b6
--- /dev/null
+++ b/Assets/Scripts/SaveSystem/SlotFileSystem.cs
@@ -0,0 +1,120 @@
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using AibisDream.Utility;
+using Newtonsoft.Json;
+using UnityEngine;
+
+namespace AibisDream.SaveSystem
+{
+    /// <summary>
+    /// 存档槽位目录与文件路径工具。
+    /// </summary>
+    public static class SlotDirectory
+    {
+        public static string GetSlotPath(int slotIndex)
+        {
+            return Path.Combine(ConstRef.SaveFilePath, $"{ConstRef.SaveSlotDirPrefix}{slotIndex}");
+        }
+
+        public static string GetSnapshotPath(int slotIndex)
+        {
+            return Path.Combine(GetSlotPath(slotIndex), $"{ConstRef.SaveSnapshotFileName}.json");
+        }
+
+        public static string GetMetaPath(int slotIndex)
+        {
+            return Path.Combine(GetSlotPath(slotIndex), $"{ConstRef.SaveMetaFileName}.json");
+        }
+
+        public static string GetThumbnailPath(int slotIndex)
+        {
+            return Path.Combine(GetSlotPath(slotIndex), $"{ConstRef.SaveThumbnailFileName}.png");
+        }
+
+        public static string GetLatestSlotIndexPath()
+        {
+            return Path.Combine(ConstRef.SaveFilePath, $"{ConstRef.LatestSlotFileName}.json");
+        }
+
+        public static bool Exists(int slotIndex)
+        {
+            return File.Exists(GetMetaPath(slotIndex));
+        }
+
+        public static IEnumerable<int> EnumerateExistingSlots()
+        {
+            if (!Directory.Exists(ConstRef.SaveFilePath))
+            {
+                yield break;
+            }
+
+            for (var i = SlotIndex.Auto; i <= SlotIndex.ManualEnd; i++)
+            {
+                if (Exists(i))
+                {
+                    yield return i;
+                }
+            }
+        }
+
+        public static void EnsureSlotDirectory(int slotIndex)
+        {
+            Directory.CreateDirectory(GetSlotPath(slotIndex));
+        }
+    }
+
+    /// <summary>
+    /// 槽位文件原子写工具。
+    /// <para>先写入临时文件，再重命名为最终文件，避免写入过程中崩溃导致存档损坏。</para>
+    /// </summary>
+    public static class SlotAtomicWriter
+    {
+        public static void WriteJson<T>(T obj, string finalPath)
+        {
+            var json = JsonConvert.SerializeObject(obj, Formatting.Indented);
+            WriteText(json, finalPath);
+        }
+
+        public static void WriteText(string text, string finalPath)
+        {
+            var tempPath = finalPath + ".tmp";
+            var dir = Path.GetDirectoryName(finalPath);
+            if (!string.IsNullOrEmpty(dir))
+            {
+                Directory.CreateDirectory(dir);
+            }
+
+            File.WriteAllText(tempPath, text);
+            CommitTempFile(tempPath, finalPath);
+        }
+
+        public static void WriteBytes(byte[] data, string finalPath)
+        {
+            if (data == null)
+            {
+                return;
+            }
+
+            var tempPath = finalPath + ".tmp";
+            var dir = Path.GetDirectoryName(finalPath);
+            if (!string.IsNullOrEmpty(dir))
+            {
+                Directory.CreateDirectory(dir);
+            }
+
+            File.WriteAllBytes(tempPath, data);
+            CommitTempFile(tempPath, finalPath);
+        }
+
+        private static void CommitTempFile(string tempPath, string finalPath)
+        {
+            if (File.Exists(finalPath))
+            {
+                File.Delete(finalPath);
+            }
+
+            File.Move(tempPath, finalPath);
+        }
+    }
+}
diff --git a/Assets/Scripts/SaveSystem/SlotFileSystem.cs.meta b/Assets/Scripts/SaveSystem/SlotFileSystem.cs.meta
new file mode 100644
index 000000000..0bf2766fd
--- /dev/null
+++ b/Assets/Scripts/SaveSystem/SlotFileSystem.cs.meta
@@ -0,0 +1,11 @@
+fileFormatVersion: 2
+guid: d819a034669842418c5e6b63b4a67cd3
+MonoImporter:
+  externalObjects: {}
+  serializedVersion: 2
+  defaultReferences: []
+  executionOrder: 0
+  icon: {instanceID: 0}
+  userData:
+  assetBundleName:
+  assetBundleVariant:
diff --git a/Assets/Scripts/SaveSystem/SlotManager.cs b/Assets/Scripts/SaveSystem/SlotManager.cs
new file mode 100644
index 000000000..78f5373f9
--- /dev/null
+++ b/Assets/Scripts/SaveSystem/SlotManager.cs
@@ -0,0 +1,381 @@
+using System;
+using System.IO;
+using System.Collections.Generic;
+using AibisDream.Utility;
+using Newtonsoft.Json;
+using UnityEngine;
+
+namespace AibisDream.SaveSystem
+{
+    /// <summary>
+    /// 存档槽位业务核心：管理自动档、手动档、读档、继续游戏与 P1 迁移。
+    /// </summary>
+    public static class SlotManager
+    {
+        private static bool _migrated;
+
+        /// <summary>将快照与缩略图写入指定槽位。</summary>
+        public static void SaveToSlot(int slotIndex, SaveSnapshot snapshot, byte[] thumbnailPng)
+        {
+            EnsureMigrated();
+            WriteSlot(slotIndex, snapshot, thumbnailPng);
+        }
+
+        /// <summary>将快照与缩略图写入自动档（slot 0）。</summary>
+        public static void SaveToAutoSlot(SaveSnapshot snapshot, byte[] thumbnailPng)
+        {
+            SaveToSlot(SlotIndex.Auto, snapshot, thumbnailPng);
+            SetLatestSlotIndex(SlotIndex.Auto);
+            CloudSaveManager.OnSlotWritten(SlotIndex.Auto);
+        }
+
+        /// <summary>将当前自动档复制到指定手动档。</summary>
+        public static void CopyAutoToManual(int manualSlotIndex)
+        {
+            EnsureMigrated();
+
+            if (manualSlotIndex < SlotIndex.ManualStart || manualSlotIndex > SlotIndex.ManualEnd)
+            {
+                Debug.LogError($"[SlotManager] 手动槽位编号非法: {manualSlotIndex}");
+                return;
+            }
+
+            if (!SlotDirectory.Exists(SlotIndex.Auto))
+            {
+                Debug.LogError("[SlotManager] 自动档不存在，无法复制手动档。");
+                return;
+            }
+
+            SlotDirectory.EnsureSlotDirectory(manualSlotIndex);
+
+            var sourceDir = SlotDirectory.GetSlotPath(SlotIndex.Auto);
+            var targetDir = SlotDirectory.GetSlotPath(manualSlotIndex);
+
+            CopyFileIfExists(
+                Path.Combine(sourceDir, $"{ConstRef.SaveSnapshotFileName}.json"),
+                Path.Combine(targetDir, $"{ConstRef.SaveSnapshotFileName}.json"));
+            CopyFileIfExists(
+                Path.Combine(sourceDir, $"{ConstRef.SaveMetaFileName}.json"),
+                Path.Combine(targetDir, $"{ConstRef.SaveMetaFileName}.json"));
+            CopyFileIfExists(
+                Path.Combine(sourceDir, $"{ConstRef.SaveThumbnailFileName}.png"),
+                Path.Combine(targetDir, $"{ConstRef.SaveThumbnailFileName}.png"));
+
+            // 修正 meta 中的 slotIndex 为手动档编号
+            var meta = LoadMeta(manualSlotIndex);
+            if (meta != null)
+            {
+                meta.slotIndex = manualSlotIndex;
+                WriteMeta(manualSlotIndex, meta);
+            }
+
+            SetLatestSlotIndex(manualSlotIndex);
+            CloudSaveManager.OnSlotWritten(manualSlotIndex);
+
+            Debug.Log($"[SlotManager] 已复制自动档到手动槽位 {manualSlotIndex}。");
+        }
+
+        /// <summary>删除指定槽位。</summary>
+        public static void DeleteSlot(int slotIndex)
+        {
+            EnsureMigrated();
+
+            if (slotIndex == SlotIndex.Auto)
+            {
+                // 自动档只清空内容，不删除目录
+                DeleteSlotFiles(slotIndex);
+                Debug.Log("[SlotManager] 已清空自动档。");
+                return;
+            }
+
+            if (slotIndex < SlotIndex.ManualStart || slotIndex > SlotIndex.ManualEnd)
+            {
+                Debug.LogError($"[SlotManager] 槽位编号非法: {slotIndex}");
+                return;
+            }
+
+            var dir = SlotDirectory.GetSlotPath(slotIndex);
+            if (Directory.Exists(dir))
+            {
+                Directory.Delete(dir, recursive: true);
+                Debug.Log($"[SlotManager] 已删除槽位 {slotIndex}。");
+            }
+
+            CloudSaveManager.OnSlotWritten(slotIndex);
+        }
+
+        /// <summary>读取槽位的完整快照。</summary>
+        public static SaveSnapshot LoadSnapshot(int slotIndex)
+        {
+            EnsureMigrated();
+
+            var path = SlotDirectory.GetSnapshotPath(slotIndex);
+            if (!File.Exists(path))
+            {
+                return null;
+            }
+
+            try
+            {
+                var json = File.ReadAllText(path);
+                return SnapshotPersistence.Deserialize(json);
+            }
+            catch (Exception ex)
+            {
+                Debug.LogError($"[SlotManager] 读取槽位 {slotIndex} 快照失败: {ex.Message}");
+                return null;
+            }
+        }
+
+        /// <summary>读取槽位元数据。</summary>
+        public static SlotMeta LoadMeta(int slotIndex)
+        {
+            var path = SlotDirectory.GetMetaPath(slotIndex);
+            if (!File.Exists(path))
+            {
+                return null;
+            }
+
+            try
+            {
+                var json = File.ReadAllText(path);
+                return JsonConvert.DeserializeObject<SlotMeta>(json);
+            }
+            catch (Exception ex)
+            {
+                Debug.LogWarning($"[SlotManager] 读取槽位 {slotIndex} meta 失败: {ex.Message}");
+                return null;
+            }
+        }
+
+        /// <summary>读取槽位缩略图字节。</summary>
+        public static byte[] LoadThumbnail(int slotIndex)
+        {
+            var path = SlotDirectory.GetThumbnailPath(slotIndex);
+            if (!File.Exists(path))
+            {
+                return null;
+            }
+
+            try
+            {
+                return File.ReadAllBytes(path);
+            }
+            catch (Exception ex)
+            {
+                Debug.LogWarning($"[SlotManager] 读取槽位 {slotIndex} 缩略图失败: {ex.Message}");
+                return null;
+            }
+        }
+
+        /// <summary>获取最近写入的槽位编号；不存在返回 null。</summary>
+        public static int? GetLatestSlotIndex()
+        {
+            EnsureMigrated();
+
+            var path = SlotDirectory.GetLatestSlotIndexPath();
+            if (!File.Exists(path))
+            {
+                return null;
+            }
+
+            try
+            {
+                var json = File.ReadAllText(path);
+                var record = JsonConvert.DeserializeObject<LatestSlotRecord>(json);
+                if (record != null && SlotDirectory.Exists(record.latestSlot))
+                {
+                    return record.latestSlot;
+                }
+            }
+            catch (Exception ex)
+            {
+                Debug.LogWarning($"[SlotManager] 读取 latest_slot 失败: {ex.Message}");
+            }
+
+            return null;
+        }
+
+        /// <summary>更新最近写入槽位索引。</summary>
+        public static void SetLatestSlotIndex(int slotIndex)
+        {
+            var record = new LatestSlotRecord
+            {
+                latestSlot = slotIndex,
+                updatedAt = DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss")
+            };
+            SlotAtomicWriter.WriteJson(record, SlotDirectory.GetLatestSlotIndexPath());
+        }
+
+        /// <summary>获取供 UI 展示的全部槽位视图模型。</summary>
+        public static SlotViewModel[] GetSlotViewModels()
+        {
+            EnsureMigrated();
+
+            var result = new List<SlotViewModel>();
+            for (var i = SlotIndex.Auto; i <= SlotIndex.ManualEnd; i++)
+            {
+                result.Add(BuildViewModel(i));
+            }
+
+            return result.ToArray();
+        }
+
+        #region Private Helpers
+
+        private static void WriteSlot(int slotIndex, SaveSnapshot snapshot, byte[] thumbnailPng)
+        {
+            SlotDirectory.EnsureSlotDirectory(slotIndex);
+
+            // snapshot.json
+            var snapshotPath = SlotDirectory.GetSnapshotPath(slotIndex);
+            var json = SnapshotPersistence.Serialize(snapshot);
+            SlotAtomicWriter.WriteText(json, snapshotPath);
+
+            // meta.json
+            var summary = SaveSnapshotSummary.From(snapshot);
+            var meta = new SlotMeta
+            {
+                slotIndex = slotIndex,
+                savedAt = snapshot.savedAt,
+                sceneName = summary.SceneName,
+                sceneSoName = summary.SceneSoName,
+                yarnProjectId = summary.YarnProjectId,
+                schemaVersion = snapshot.schemaVersion,
+                gameVersion = snapshot.gameVersion,
+                thumbnailFile = $"{ConstRef.SaveThumbnailFileName}.png"
+            };
+            WriteMeta(slotIndex, meta);
+
+            // thumbnail.png
+            if (thumbnailPng != null)
+            {
+                SlotAtomicWriter.WriteBytes(thumbnailPng, SlotDirectory.GetThumbnailPath(slotIndex));
+            }
+        }
+
+        private static void WriteMeta(int slotIndex, SlotMeta meta)
+        {
+            SlotAtomicWriter.WriteJson(meta, SlotDirectory.GetMetaPath(slotIndex));
+        }
+
+        private static void CopyFileIfExists(string sourcePath, string targetPath)
+        {
+            if (!File.Exists(sourcePath))
+            {
+                return;
+            }
+
+            var dir = Path.GetDirectoryName(targetPath);
+            if (!string.IsNullOrEmpty(dir))
+            {
+                Directory.CreateDirectory(dir);
+            }
+
+            File.Copy(sourcePath, targetPath, overwrite: true);
+        }
+
+        private static void DeleteSlotFiles(int slotIndex)
+        {
+            var dir = SlotDirectory.GetSlotPath(slotIndex);
+            if (!Directory.Exists(dir))
+            {
+                return;
+            }
+
+            foreach (var file in Directory.GetFiles(dir))
+            {
+                File.Delete(file);
+            }
+        }
+
+        private static SlotViewModel BuildViewModel(int slotIndex)
+        {
+            var meta = LoadMeta(slotIndex);
+            if (meta == null)
+            {
+                return new SlotViewModel(
+                    slotIndex,
+                    isEmpty: true,
+                    isAutoSlot: slotIndex == SlotIndex.Auto,
+                    savedAt: null,
+                    sceneName: null,
+                    sceneSoName: null,
+                    thumbnailPath: null);
+            }
+
+            var thumbnailPath = SlotDirectory.GetThumbnailPath(slotIndex);
+            if (!File.Exists(thumbnailPath))
+            {
+                thumbnailPath = null;
+            }
+
+            return new SlotViewModel(
+                slotIndex,
+                isEmpty: false,
+                isAutoSlot: slotIndex == SlotIndex.Auto,
+                savedAt: meta.savedAt,
+                sceneName: meta.sceneName,
+                sceneSoName: meta.sceneSoName,
+                thumbnailPath: thumbnailPath);
+        }
+
+        private static void EnsureMigrated()
+        {
+            if (_migrated)
+            {
+                return;
+            }
+
+            _migrated = true;
+            TryMigrateP1TestSnapshot();
+        }
+
+        private static void TryMigrateP1TestSnapshot()
+        {
+            var testPath = Path.Combine(ConstRef.SnapshotTestPath, $"{ConstRef.SnapshotTestFileName}.json");
+            if (!File.Exists(testPath))
+            {
+                return;
+            }
+
+            if (SlotDirectory.Exists(SlotIndex.Auto))
+            {
+                return;
+            }
+
+            try
+            {
+                var snapshot = SnapshotPersistence.Load(testPath);
+                if (snapshot == null)
+                {
+                    return;
+                }
+
+                SaveToAutoSlot(snapshot, null);
+
+                var migratedPath = testPath + ".migrated";
+                if (File.Exists(migratedPath))
+                {
+                    File.Delete(migratedPath);
+                }
+                File.Move(testPath, migratedPath);
+
+                Debug.Log($"[SlotManager] 已将 P1 测试存档从 {testPath} 迁移到 slot_0。");
+            }
+            catch (Exception ex)
+            {
+                Debug.LogWarning($"[SlotManager] P1 测试存档迁移失败: {ex.Message}");
+            }
+        }
+
+        [Serializable]
+        private class LatestSlotRecord
+        {
+            public int latestSlot;
+            public string updatedAt;
+        }
+
+        #endregion
+    }
+}
diff --git a/Assets/Scripts/SaveSystem/SlotManager.cs.meta b/Assets/Scripts/SaveSystem/SlotManager.cs.meta
new file mode 100644
index 000000000..14cb7c7d8
--- /dev/null
+++ b/Assets/Scripts/SaveSystem/SlotManager.cs.meta
@@ -0,0 +1,11 @@
+fileFormatVersion: 2
+guid: af4d8624a0d645ce9b07f73024290cd6
+MonoImporter:
+  externalObjects: {}
+  serializedVersion: 2
+  defaultReferences: []
+  executionOrder: 0
+  icon: {instanceID: 0}
+  userData:
+  assetBundleName:
+  assetBundleVariant:
diff --git a/Assets/Scripts/SaveSystem/SlotThumbnailCapture.cs b/Assets/Scripts/SaveSystem/SlotThumbnailCapture.cs
new file mode 100644
index 000000000..3d4b3561d
--- /dev/null
+++ b/Assets/Scripts/SaveSystem/SlotThumbnailCapture.cs
@@ -0,0 +1,48 @@
+using AibisDream.Utility;
+using UnityEngine;
+
+namespace AibisDream.SaveSystem
+{
+    /// <summary>
+    /// 存档槽位缩略图捕获工具。
+    /// <para>
+    /// 使用主相机渲染到 RenderTexture 后读像素并编码为 PNG。
+    /// 捕获失败时安全返回 null，不会阻塞存档流程。
+    /// </para>
+    /// </summary>
+    public static class SlotThumbnailCapture
+    {
+        /// <summary>捕获当前画面的 PNG 字节数组。</summary>
+        public static byte[] CapturePng()
+        {
+            var cam = Camera.main;
+            if (cam == null)
+            {
+                Debug.LogWarning("[SlotThumbnailCapture] 未找到 Camera.main，跳过截图。");
+                return null;
+            }
+
+            var width = ConstRef.SaveThumbnailWidth;
+            var height = ConstRef.SaveThumbnailHeight;
+
+            var rt = RenderTexture.GetTemporary(width, height, 24, RenderTextureFormat.Default);
+            var prevTarget = cam.targetTexture;
+            cam.targetTexture = rt;
+            cam.Render();
+            cam.targetTexture = prevTarget;
+
+            RenderTexture.active = rt;
+            var tex = new Texture2D(width, height, TextureFormat.RGB24, false);
+            tex.ReadPixels(new Rect(0, 0, width, height), 0, 0);
+            tex.Apply();
+            RenderTexture.active = null;
+
+            var bytes = tex.EncodeToPNG();
+
+            Object.Destroy(tex);
+            RenderTexture.ReleaseTemporary(rt);
+
+            return bytes;
+        }
+    }
+}
diff --git a/Assets/Scripts/SaveSystem/SlotThumbnailCapture.cs.meta b/Assets/Scripts/SaveSystem/SlotThumbnailCapture.cs.meta
new file mode 100644
index 000000000..41a496b69
--- /dev/null
+++ b/Assets/Scripts/SaveSystem/SlotThumbnailCapture.cs.meta
@@ -0,0 +1,11 @@
+fileFormatVersion: 2
+guid: 63f375c0f57444058bef24100d912ece
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+  externalObjects: {}
+  serializedVersion: 2
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diff --git a/Assets/Scripts/SaveSystem/SlotTypes.cs b/Assets/Scripts/SaveSystem/SlotTypes.cs
new file mode 100644
index 000000000..b7c3ae0bf
--- /dev/null
+++ b/Assets/Scripts/SaveSystem/SlotTypes.cs
@@ -0,0 +1,60 @@
+using System;
+
+namespace AibisDream.SaveSystem
+{
+    /// <summary>
+    /// 存档槽位编号常量。
+    /// <para>slot_0 为自动档；slot_1..slot_8 为手动档。</para>
+    /// </summary>
+    public static class SlotIndex
+    {
+        public const int Auto = 0;
+        public const int ManualStart = 1;
+        public const int ManualEnd = 8;
+        public const int ManualSlotCount = ManualEnd - ManualStart + 1;
+    }
+
+    /// <summary>
+    /// 单个存档槽位的轻量 sidecar 元数据。
+    /// <para>与完整 <see cref="SaveSnapshot"/> 分离，避免 UI 枚举槽位时反复解析大 JSON。</para>
+    /// </summary>
+    [Serializable]
+    public class SlotMeta
+    {
+        public int slotIndex;
+        public string savedAt;
+        public string sceneName;
+        public string sceneSoName;
+        public string yarnProjectId;
+        public int schemaVersion;
+        public string gameVersion;
+        public string thumbnailFile;
+    }
+
+    /// <summary>
+    /// 存档槽位 UI 展示用的只读数据契约。
+    /// <para>由 <see cref="SlotManager.GetSlotViewModels"/> 产出，供 P6 的 SlotPanel 消费。</para>
+    /// </summary>
+    public readonly struct SlotViewModel
+    {
+        public readonly int SlotIndex;
+        public readonly bool IsEmpty;
+        public readonly bool IsAutoSlot;
+        public readonly string SavedAt;
+        public readonly string SceneName;
+        public readonly string SceneSoName;
+        public readonly string ThumbnailPath;
+
+        public SlotViewModel(int slotIndex, bool isEmpty, bool isAutoSlot, string savedAt,
+            string sceneName, string sceneSoName, string thumbnailPath)
+        {
+            SlotIndex = slotIndex;
+            IsEmpty = isEmpty;
+            IsAutoSlot = isAutoSlot;
+            SavedAt = savedAt;
+            SceneName = sceneName;
+            SceneSoName = sceneSoName;
+            ThumbnailPath = thumbnailPath;
+        }
+    }
+}
diff --git a/Assets/Scripts/SaveSystem/SlotTypes.cs.meta b/Assets/Scripts/SaveSystem/SlotTypes.cs.meta
new file mode 100644
index 000000000..e38018807
--- /dev/null
+++ b/Assets/Scripts/SaveSystem/SlotTypes.cs.meta
@@ -0,0 +1,11 @@
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