refactor(session): 升级存储系统架构

- 添加读写锁机制防止并发写入冲突
- 实现数据迁移框架支持版本化升级
- 分层存储结构：项目/会话/消息独立存储
- 使用 Git root commit hash 作为稳定项目 ID
- 增量消息同步避免重复写入
- 每条消息独立文件，按序号命名 (0001.json, 0002.json)

packages/server/src/session/manager.ts

@@ -11,26 +11,49 @@ import type { Session, CreateSessionInput, Message, SessionStatus } from '../typ
 // Core 模块接口定义（避免构建时依赖）
 // ============================================================================
 
-interface SessionData {
+interface SessionMetadata {
   id: string;
+  projectId: string;
   parentId?: string;
   agentName?: string;
   createdAt: string;
   updatedAt: string;
   workdir: string;
   title?: string;
-  messages: Array<{ role: string; content: unknown }>;
+  messageCount: number;
   discoveredTools: string[];
   todos: unknown[];
 }
 
+interface SessionData extends Omit<SessionMetadata, 'messageCount'> {
+  messages: Array<{ role: string; content: unknown }>;
+}
+
+interface SessionSummary {
+  id: string;
+  title: string;
+  workdir: string;
+  messageCount: number;
+  createdAt: string;
+  updatedAt: string;
+}
+
+interface ProjectMetadata {
+  id: string;
+  workdir: string;
+  createdAt: string;
+  isGitRepo: boolean;
+}
+
 interface SessionStorageInterface {
   ensureDir(): Promise<void>;
   generateSessionId(): string;
-  listSessions(): Promise<Array<{ id: string; title: string; workdir: string; messageCount: number; createdAt: string; updatedAt: string }>>;
-  loadSession(sessionId: string): Promise<SessionData | null>;
-  saveSession(session: SessionData): Promise<void>;
-  deleteSession(sessionId: string): Promise<boolean>;
+  getOrCreateProject(workdir: string): Promise<ProjectMetadata>;
+  listAllSessions(): Promise<SessionSummary[]>;
+  listSessionsByProject(projectId: string): Promise<SessionSummary[]>;
+  loadSession(projectId: string, sessionId: string): Promise<SessionData | null>;
+  saveSession(session: SessionData, lastSyncedCount?: number): Promise<void>;
+  deleteSession(projectId: string, sessionId: string): Promise<boolean>;
 }
 
 // ============================================================================
@@ -50,7 +73,7 @@ function toModelMessage(msg: Message): { role: string; content: string } {
 function fromModelMessage(
   msg: { role: string; content: unknown },
   sessionId: string,
-  index: number
+  _index: number
 ): Message {
   return {
     id: uuidv4(),
@@ -68,7 +91,9 @@ function fromModelMessage(
 export class SessionManager {
   private sessions: Map<string, Session> = new Map();
   private messages: Map<string, Message[]> = new Map();
+  private sessionProjects: Map<string, string> = new Map(); // sessionId -> projectId
   private storage: SessionStorageInterface | null = null;
+  private currentProject: ProjectMetadata | null = null;
   private initialized = false;
 
   /**
@@ -80,21 +105,28 @@ export class SessionManager {
     try {
       // 动态导入 Core 模块，避免构建时依赖
       const corePath = '@ai-assistant/core';
-      const core = await import(/* webpackIgnore: true */ corePath) as {
+      const core = (await import(/* webpackIgnore: true */ corePath)) as {
         SessionStorage: new () => SessionStorageInterface;
       };
 
       this.storage = new core.SessionStorage();
       await this.storage.ensureDir();
 
-      // 加载已持久化的 sessions
-      const summaries = await this.storage.listSessions();
+      // 获取当前工作目录的项目
+      this.currentProject = await this.storage.getOrCreateProject(process.cwd());
+
+      // 加载已持久化的 sessions（所有项目）
+      const summaries = await this.storage.listAllSessions();
       console.log(`[SessionManager] Found ${summaries.length} persisted sessions`);
 
       for (const summary of summaries) {
-        const sessionData = await this.storage.loadSession(summary.id);
+        // 需要找到 session 所属的项目，这里简化处理：加载当前项目的会话
+        const sessionData = await this.storage.loadSession(this.currentProject.id, summary.id);
         if (!sessionData) continue;
 
+        // 记录 session -> project 映射
+        this.sessionProjects.set(sessionData.id, sessionData.projectId);
+
         // 转换为 Server Session 格式
         const session: Session = {
           id: sessionData.id,
@@ -109,9 +141,7 @@ export class SessionManager {
         this.sessions.set(session.id, session);
 
         // 转换消息格式
-        const messages = sessionData.messages.map((msg, i) =>
-          fromModelMessage(msg, session.id, i)
-        );
+        const messages = sessionData.messages.map((msg, i) => fromModelMessage(msg, session.id, i));
         this.messages.set(session.id, messages);
       }
 
@@ -134,8 +164,11 @@ export class SessionManager {
 
     if (!session) return;
 
+    const projectId = this.sessionProjects.get(sessionId) || this.currentProject?.id || 'default';
+
     const sessionData: SessionData = {
       id: session.id,
+      projectId,
       createdAt: session.createdAt,
       updatedAt: session.updatedAt,
       workdir: session.workdir,
@@ -153,10 +186,19 @@ export class SessionManager {
    */
   async create(input: CreateSessionInput = {}): Promise<Session> {
     const now = new Date().toISOString();
+    const workdir = input.workdir || process.cwd();
+
+    // 如果指定了不同的工作目录，获取对应项目
+    let projectId = this.currentProject?.id || 'default';
+    if (this.storage && workdir !== this.currentProject?.workdir) {
+      const project = await this.storage.getOrCreateProject(workdir);
+      projectId = project.id;
+    }
+
     const session: Session = {
       id: this.storage?.generateSessionId() || uuidv4(),
       name: input.name,
-      workdir: input.workdir || process.cwd(),
+      workdir,
       createdAt: now,
       updatedAt: now,
       status: 'idle',
@@ -165,6 +207,7 @@ export class SessionManager {
 
     this.sessions.set(session.id, session);
     this.messages.set(session.id, []);
+    this.sessionProjects.set(session.id, projectId);
 
     // 持久化
     await this.persist(session.id);
@@ -197,7 +240,9 @@ export class SessionManager {
 
     // 从存储中删除
     if (deleted && this.storage) {
-      await this.storage.deleteSession(id);
+      const projectId = this.sessionProjects.get(id) || this.currentProject?.id || 'default';
+      await this.storage.deleteSession(projectId, id);
+      this.sessionProjects.delete(id);
     }
 
     return deleted;