feat(checkpoint): 添加 Checkpoint 可视化管理功能

Core 层增强:
- 添加 safety.ts: 7点安全检查机制
- 添加 session-tracker.ts: 会话级检查点跟踪
- 添加 lock.ts: 并发控制文件锁
- 添加 lfs.ts: Git LFS 大文件支持
- 添加 path-validator.ts: 路径验证
- 添加 commit-message.ts: 智能提交消息生成
- 增强 manager.ts: 支持三种恢复模式、unrevert 撤销回滚

Server 层:
- 添加 checkpoints.ts: 16个 REST API 端点
  - GET/POST /checkpoints: 列表/创建检查点
  - GET/DELETE /checkpoints/🆔 获取/删除检查点
  - GET /checkpoints/:id/diff: 获取差异
  - POST /checkpoints/:id/restore: 恢复到检查点
  - POST /checkpoints/unrevert: 撤销回滚
  - GET /checkpoints/:id/safety-check: 安全检查

UI 层:
- 添加 CheckpointPanel.tsx: 检查点列表面板
- 添加 CheckpointDiffViewer.tsx: 差异查看器
- 添加 RestoreDialog.tsx: 恢复确认对话框
- 添加 16 个 API 客户端函数
- 添加完整的 TypeScript 类型定义

Web/Desktop 集成:
- 添加 History 按钮到工具栏
- 集成 CheckpointPanel 组件

packages/ui/src/api/client.ts

@@ -28,6 +28,16 @@ import type {
   AgentDetail,
   AgentInput,
   AgentDefaults,
+  CheckpointListItem,
+  CheckpointDetail,
+  CheckpointStats,
+  DiffInfo,
+  FileDiffDetail,
+  RestoreOptions,
+  RestoreResult,
+  SafetyCheckResult,
+  UnrevertStatus,
+  UnrevertResult,
 } from './types.js';
 
 // Re-export types
@@ -71,6 +81,21 @@ export type {
   AgentDetail,
   AgentInput,
   AgentDefaults,
+  // Checkpoint types
+  CheckpointTrigger,
+  FileChangeType,
+  CheckpointListItem,
+  CheckpointDetail,
+  FileChange,
+  DiffInfo,
+  FileDiffDetail,
+  RestoreMode,
+  RestoreOptions,
+  RestoreResult,
+  SafetyCheckResult,
+  CheckpointStats,
+  UnrevertStatus,
+  UnrevertResult,
 } from './types.js';
 
 // API Configuration
@@ -588,3 +613,194 @@ export async function updateAgentDefaults(defaults: AgentDefaults): Promise<{
 }> {
   return request('PUT', '/agents/defaults', defaults);
 }
+
+// ============ Checkpoints API ============
+
+/**
+ * 获取所有检查点列表
+ */
+export async function listCheckpoints(): Promise<{
+  success: boolean;
+  data: CheckpointListItem[];
+  error?: string;
+}> {
+  return request('GET', '/checkpoints');
+}
+
+/**
+ * 获取检查点统计信息
+ */
+export async function getCheckpointStats(): Promise<{
+  success: boolean;
+  data: CheckpointStats;
+  error?: string;
+}> {
+  return request('GET', '/checkpoints/stats');
+}
+
+/**
+ * 获取最新检查点
+ */
+export async function getLatestCheckpoint(): Promise<{
+  success: boolean;
+  data: CheckpointDetail | null;
+  error?: string;
+}> {
+  return request('GET', '/checkpoints/latest');
+}
+
+/**
+ * 获取单个检查点详情
+ */
+export async function getCheckpoint(id: string): Promise<{
+  success: boolean;
+  data?: CheckpointDetail;
+  error?: string;
+}> {
+  return request('GET', `/checkpoints/${encodeURIComponent(id)}`);
+}
+
+/**
+ * 创建手动检查点
+ */
+export async function createCheckpoint(options?: {
+  name?: string;
+  description?: string;
+}): Promise<{
+  success: boolean;
+  data?: CheckpointDetail;
+  error?: string;
+}> {
+  return request('POST', '/checkpoints', options || {});
+}
+
+/**
+ * 删除检查点
+ */
+export async function deleteCheckpoint(id: string): Promise<{
+  success: boolean;
+  data?: { deleted: boolean };
+  error?: string;
+}> {
+  return request('DELETE', `/checkpoints/${encodeURIComponent(id)}`);
+}
+
+/**
+ * 获取检查点与当前工作区的差异
+ */
+export async function getCheckpointDiff(id: string): Promise<{
+  success: boolean;
+  data?: DiffInfo;
+  error?: string;
+}> {
+  return request('GET', `/checkpoints/${encodeURIComponent(id)}/diff`);
+}
+
+/**
+ * 获取单个文件的详细差异
+ */
+export async function getFileDiff(checkpointId: string, filePath: string): Promise<{
+  success: boolean;
+  data?: FileDiffDetail;
+  error?: string;
+}> {
+  const params = new URLSearchParams({ path: filePath });
+  return request('GET', `/checkpoints/${encodeURIComponent(checkpointId)}/file-diff?${params}`);
+}
+
+/**
+ * 回滚到检查点
+ */
+export async function restoreCheckpoint(
+  id: string,
+  options?: RestoreOptions
+): Promise<{
+  success: boolean;
+  data?: RestoreResult;
+  error?: string;
+}> {
+  return request('POST', `/checkpoints/${encodeURIComponent(id)}/restore`, options || {});
+}
+
+/**
+ * 预览回滚（dry run）
+ */
+export async function previewRestore(
+  id: string,
+  options?: { mode?: RestoreOptions['mode']; files?: string[] }
+): Promise<{
+  success: boolean;
+  data?: RestoreResult;
+  error?: string;
+}> {
+  const params = new URLSearchParams();
+  if (options?.mode) params.set('mode', options.mode);
+  if (options?.files) params.set('files', options.files.join(','));
+  return request('GET', `/checkpoints/${encodeURIComponent(id)}/restore/preview?${params}`);
+}
+
+/**
+ * 撤销最近一次回滚
+ */
+export async function unrevert(): Promise<{
+  success: boolean;
+  data?: UnrevertResult;
+  error?: string;
+}> {
+  return request('POST', '/checkpoints/unrevert');
+}
+
+/**
+ * 检查是否可撤销回滚
+ */
+export async function getUnrevertStatus(): Promise<{
+  success: boolean;
+  data?: UnrevertStatus;
+  error?: string;
+}> {
+  return request('GET', '/checkpoints/unrevert/status');
+}
+
+/**
+ * 执行安全检查
+ */
+export async function checkSafety(id: string): Promise<{
+  success: boolean;
+  data?: SafetyCheckResult;
+  error?: string;
+}> {
+  return request('GET', `/checkpoints/${encodeURIComponent(id)}/safety-check`);
+}
+
+/**
+ * 清理过期检查点
+ */
+export async function cleanupCheckpoints(): Promise<{
+  success: boolean;
+  data?: { deleted: number };
+  error?: string;
+}> {
+  return request('POST', '/checkpoints/cleanup');
+}
+
+/**
+ * 获取会话的所有检查点
+ */
+export async function getSessionCheckpoints(sessionId: string): Promise<{
+  success: boolean;
+  data: CheckpointListItem[];
+  error?: string;
+}> {
+  return request('GET', `/checkpoints/sessions/${encodeURIComponent(sessionId)}`);
+}
+
+/**
+ * 获取消息关联的检查点
+ */
+export async function getMessageCheckpoints(messageId: string): Promise<{
+  success: boolean;
+  data: CheckpointListItem[];
+  error?: string;
+}> {
+  return request('GET', `/checkpoints/messages/${encodeURIComponent(messageId)}`);
+}