feat: 添加完整的单元测试套件

- 新增 vitest 测试框架配置
- 添加 54 个测试文件，共 951 个测试用例
- 覆盖核心模块：
  - Agent: executor, registry, config-loader, permission-merger
  - Context: manager, compaction, prune, token-counter
  - Permission: manager, bash/file/git/web checkers, wildcard
  - Session: manager, storage
  - Tools: filesystem (12个), git (10个), web, shell, todo, task
  - LSP: client, server, language
  - Utils: config, diff
  - UI: terminal

tests/unit/tools/todo/todowrite.test.ts

@@ -0,0 +1,171 @@
+import { describe, it, expect, beforeEach, vi } from 'vitest';
+
+// 使用可变的引用对象来绕过 hoisting 问题
+const mockState = {
+  isInitialized: vi.fn().mockReturnValue(true),
+  getTodos: vi.fn().mockReturnValue([]),
+  setTodos: vi.fn().mockResolvedValue(undefined),
+};
+
+vi.mock('../../../../src/tools/todo/todo-manager.js', () => ({
+  todoManager: {
+    isInitialized: () => mockState.isInitialized(),
+    getTodos: () => mockState.getTodos(),
+    setTodos: (todos: any) => mockState.setTodos(todos),
+  },
+}));
+
+import { todoWriteTool } from '../../../../src/tools/todo/todowrite.js';
+
+describe('todoWriteTool - Todo 写入工具', () => {
+  beforeEach(() => {
+    vi.clearAllMocks();
+    mockState.isInitialized.mockReturnValue(true);
+    mockState.getTodos.mockReturnValue([]);
+  });
+
+  describe('工具定义', () => {
+    it('有正确的名称', () => {
+      expect(todoWriteTool.name).toBe('todowrite');
+    });
+
+    it('有正确的元数据', () => {
+      expect(todoWriteTool.metadata.category).toBe('core');
+      expect(todoWriteTool.metadata.keywords).toContain('todo');
+      expect(todoWriteTool.metadata.keywords).toContain('task');
+      expect(todoWriteTool.metadata.keywords).toContain('write');
+    });
+
+    it('定义了必需的 todos 参数', () => {
+      expect(todoWriteTool.parameters.todos.required).toBe(true);
+    });
+  });
+
+  describe('execute - 执行', () => {
+    it('成功创建待办列表', async () => {
+      const result = await todoWriteTool.execute({
+        todos: [
+          { content: '任务1', status: 'pending' },
+          { content: '任务2', status: 'in_progress' },
+        ],
+      });
+
+      expect(result.success).toBe(true);
+      expect(result.output).toContain('待办事项已更新');
+      expect(mockState.setTodos).toHaveBeenCalled();
+    });
+
+    it('返回正确的统计信息', async () => {
+      const result = await todoWriteTool.execute({
+        todos: [
+          { content: '任务1', status: 'pending' },
+          { content: '任务2', status: 'in_progress' },
+          { content: '任务3', status: 'completed' },
+        ],
+      });
+
+      expect(result.success).toBe(true);
+      // pendingCount 包含所有非 completed 状态的任务（pending + in_progress）
+      expect(result.metadata?.pendingCount).toBe(2);
+      expect(result.metadata?.inProgressCount).toBe(1);
+      expect(result.metadata?.completedCount).toBe(1);
+    });
+
+    it('更新现有任务', async () => {
+      mockState.getTodos.mockReturnValue([
+        { id: 'existing-1', content: '任务1', status: 'pending', createdAt: '2024-01-01', updatedAt: '2024-01-01' },
+      ]);
+
+      const result = await todoWriteTool.execute({
+        todos: [
+          { content: '任务1', status: 'completed' },
+        ],
+      });
+
+      expect(result.success).toBe(true);
+      const savedTodos = mockState.setTodos.mock.calls[0][0];
+      expect(savedTodos[0].id).toBe('existing-1'); // 保留原有 ID
+      expect(savedTodos[0].status).toBe('completed');
+    });
+
+    it('未初始化时返回错误', async () => {
+      mockState.isInitialized.mockReturnValue(false);
+
+      const result = await todoWriteTool.execute({
+        todos: [{ content: '任务', status: 'pending' }],
+      });
+
+      expect(result.success).toBe(false);
+      expect(result.error).toContain('会话管理器未初始化');
+    });
+
+    it('todos 非数组返回错误', async () => {
+      const result = await todoWriteTool.execute({
+        todos: 'not an array',
+      });
+
+      expect(result.success).toBe(false);
+      expect(result.error).toContain('todos 参数必须是数组');
+    });
+
+    it('无效的待办项格式返回错误', async () => {
+      const result = await todoWriteTool.execute({
+        todos: [
+          { content: '有效任务', status: 'pending' },
+          { content: '', status: 'pending' }, // 空内容
+        ],
+      });
+
+      expect(result.success).toBe(false);
+      expect(result.error).toContain('第 2 个待办事项格式无效');
+    });
+
+    it('无效的状态值返回错误', async () => {
+      const result = await todoWriteTool.execute({
+        todos: [
+          { content: '任务', status: 'invalid_status' },
+        ],
+      });
+
+      expect(result.success).toBe(false);
+      expect(result.error).toContain('格式无效');
+    });
+
+    it('缺少 content 返回错误', async () => {
+      const result = await todoWriteTool.execute({
+        todos: [
+          { status: 'pending' },
+        ],
+      });
+
+      expect(result.success).toBe(false);
+      expect(result.error).toContain('格式无效');
+    });
+
+    it('为新任务生成 ID', async () => {
+      const result = await todoWriteTool.execute({
+        todos: [
+          { content: '新任务', status: 'pending' },
+        ],
+      });
+
+      expect(result.success).toBe(true);
+      const savedTodos = mockState.setTodos.mock.calls[0][0];
+      expect(savedTodos[0].id).toBeDefined();
+      expect(savedTodos[0].id.length).toBeGreaterThan(0);
+    });
+
+    it('设置创建和更新时间', async () => {
+      const result = await todoWriteTool.execute({
+        todos: [
+          { content: '新任务', status: 'pending' },
+        ],
+      });
+
+      expect(result.success).toBe(true);
+      const savedTodos = mockState.setTodos.mock.calls[0][0];
+      expect(savedTodos[0].createdAt).toBeDefined();
+      expect(savedTodos[0].updatedAt).toBeDefined();
+    });
+  });
+});