feat(workflow): add workflow engine, /workflows panel, /ultracode skill

将 feat/sdk-backend 分支中 workflow 相关的 20 个 commit 压缩为单 commit：

- 工作流引擎核心：phase / agent / parallel / pipeline 编排原语（packages/workflow-engine/）
- /workflows 面板：三区焦点布局（顶部 run tabs + 左侧 phase 侧栏 + 右侧 agent 列表）
- /ultracode skill：多 agent workflow 编排入口
- 进度存储 / journal / notification 系统
- WorkflowService 生命周期管理 + SentryErrorBoundary
- 脚本沙箱：禁用 dynamic import()、JSON args 防御性归一化
- journal 与 named-workflow 路径统一在 projectRoot
- 错误处理：parallel/pipeline hooks 错误日志、failure routing、semaphore abort
- workflow 工具升级为 core 工具 + PascalCase 命名

Co-Authored-By: glm-5.1 <zai-org@claude-code-best.win>

bun.lock

@@ -332,6 +332,17 @@
         "qrcode": "^1.5.4",
       },
     },
+    "packages/workflow-engine": {
+      "name": "@claude-code-best/workflow-engine",
+      "version": "0.1.0",
+      "dependencies": {
+        "ajv": "^8.18.0",
+        "zod": "^4.3.6",
+      },
+      "devDependencies": {
+        "@anthropic-ai/sdk": "^0.81.0",
+      },
+    },
   },
   "overrides": {
     "@inquirer/prompts": "8.4.2",
@@ -586,6 +597,8 @@
 
     "@claude-code-best/weixin": ["@claude-code-best/weixin@workspace:packages/weixin"],
 
+    "@claude-code-best/workflow-engine": ["@claude-code-best/workflow-engine@workspace:packages/workflow-engine"],
+
     "@commander-js/extra-typings": ["@commander-js/extra-typings@14.0.0", "https://registry.npmmirror.com/@commander-js/extra-typings/-/extra-typings-14.0.0.tgz", { "peerDependencies": { "commander": "~14.0.0" } }, "sha512-hIn0ncNaJRLkZrxBIp5AsW/eXEHNKYQBh0aPdoUqNgD+Io3NIykQqpKFyKcuasZhicGaEZJX/JBSIkZ4e5x8Dg=="],
 
     "@emnapi/core": ["@emnapi/core@1.9.2", "https://registry.npmmirror.com/@emnapi/core/-/core-1.9.2.tgz", { "dependencies": { "@emnapi/wasi-threads": "1.2.1", "tslib": "^2.4.0" } }, "sha512-UC+ZhH3XtczQYfOlu3lNEkdW/p4dsJ1r/bP7H8+rhao3TTTMO1ATq/4DdIi23XuGoFY+Cz0JmCbdVl0hz9jZcA=="],