feat(phase4-5): add Workflow types and expand Skills ecosystem

Phase 4: Type System Completion (P2)
- Add comprehensive Workflow type definitions:
  - WorkflowStepType: hand, skill, agent, condition, parallel, delay
  - WorkflowStep: individual step configuration
  - Workflow: complete workflow definition
  - WorkflowRunStatus: pending, running, completed, failed, cancelled, paused
  - WorkflowRun: execution instance tracking
  - Request/Response types for API operations
  - Control types for pause/resume/cancel
- Update types/index.ts with workflow exports

Phase 5: Skills Ecosystem Expansion (P2)
- Add 5 new Skills with SKILL.md definitions:
  - git: Git version control operations
  - file-operations: File system operations
  - web-search: Web search capabilities
  - data-analysis: Data analysis and visualization
  - shell-command: Shell command execution
- Skills coverage now at 9/60+ (15%)

Documentation:
- Update SYSTEM_ANALYSIS.md Phase 4 & 5 status
- Mark Phase 4 as completed
- Update Phase 5 progress tracking

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

skills/git/SKILL.md

@@ -0,0 +1,131 @@
+---
+name: git
+description: Git 版本控制操作 - 执行提交、推送、拉取、分支管理等 Git 操作
+triggers:
+  - "git"
+  - "提交"
+  - "commit"
+  - "push"
+  - "pull"
+  - "分支"
+  - "branch"
+  - "合并"
+  - "merge"
+  - "rebase"
+  - "暂存"
+  - "stash"
+tools:
+  - bash
+---
+
+# Git 版本控制操作
+
+执行 Git 版本控制操作，管理代码仓库的版本历史。
+
+## 能力
+
+- 提交代码：创建新的 commit
+- 推送代码：将本地更改推送到远程仓库
+- 拉取代码：从远程仓库获取最新更改
+- 分支管理：创建、切换、删除分支
+- 合并代码：合并分支，处理冲突
+- 查看历史：查看提交日志、文件变更
+- 暂存更改：stash 相关操作
+
+## 工具依赖
+
+- bash: 执行 git 命令
+
+## 常用命令
+
+### 提交相关
+
+```bash
+# 查看状态
+git status
+
+# 添加文件
+git add <file>
+git add .
+
+# 提交
+git commit -m "type(scope): message"
+
+# 推送
+git push origin <branch>
+```
+
+### 分支相关
+
+```bash
+# 查看分支
+git branch -a
+
+# 创建分支
+git checkout -b <new-branch>
+
+# 切换分支
+git checkout <branch>
+
+# 删除分支
+git branch -d <branch>
+```
+
+### 合并相关
+
+```bash
+# 合并分支
+git merge <branch>
+
+# rebase
+git rebase <branch>
+
+# 处理冲突后继续
+git rebase --continue
+```
+
+## 提交信息规范
+
+遵循 Conventional Commits 格式：
+
+```
+<type>(<scope>): <description>
+
+[optional body]
+
+[optional footer]
+```
+
+### 类型 (type)
+
+| 类型 | 说明 |
+|------|------|
+| feat | 新功能 |
+| fix | 修复 bug |
+| docs | 文档更新 |
+| style | 代码格式（不影响功能） |
+| refactor | 重构 |
+| perf | 性能优化 |
+| test | 测试相关 |
+| chore | 构建/工具相关 |
+| ci | CI/CD 相关 |
+
+## 示例用法
+
+```
+用户: 帮我提交这些更改，提交信息是 "feat(auth): add OAuth2 login"
+助手: 执行提交操作...
+
+$ git add .
+$ git commit -m "feat(auth): add OAuth2 login"
+$ git push origin main
+
+提交成功！
+```
+
+## 输出规范
+
+- 显示执行的 git 命令
+- 显示命令输出结果
+- 遇到错误时提供解决建议
+- 中文描述操作结果