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/filesystem/search_files.test.ts

@@ -0,0 +1,199 @@
+import { describe, it, expect, beforeEach, vi } from 'vitest';
+
+// Mock fs/promises
+vi.mock('fs/promises', () => ({
+  readdir: vi.fn(),
+}));
+
+// Mock permission manager
+vi.mock('../../../../src/permission/index.js', () => ({
+  getPermissionManager: vi.fn(() => ({
+    checkFilePermission: vi.fn().mockResolvedValue({
+      allowed: true,
+      action: 'allow',
+    }),
+  })),
+}));
+
+// Mock loadDescription
+vi.mock('../../../../src/tools/load_description.js', () => ({
+  loadDescription: vi.fn(() => '按文件名搜索文件'),
+}));
+
+import { searchFilesTool } from '../../../../src/tools/filesystem/search_files.js';
+import * as fs from 'fs/promises';
+import { getPermissionManager } from '../../../../src/permission/index.js';
+
+describe('searchFilesTool - 文件搜索工具', () => {
+  beforeEach(() => {
+    vi.clearAllMocks();
+  });
+
+  describe('工具定义', () => {
+    it('有正确的名称', () => {
+      expect(searchFilesTool.name).toBe('search_files');
+    });
+
+    it('有正确的元数据', () => {
+      expect(searchFilesTool.metadata.category).toBe('filesystem');
+      expect(searchFilesTool.metadata.keywords).toContain('search');
+      expect(searchFilesTool.metadata.keywords).toContain('find');
+      expect(searchFilesTool.metadata.keywords).toContain('glob');
+    });
+
+    it('定义了必需参数', () => {
+      expect(searchFilesTool.parameters.directory.required).toBe(true);
+      expect(searchFilesTool.parameters.pattern.required).toBe(true);
+    });
+  });
+
+  describe('execute - 执行', () => {
+    it('成功搜索并返回匹配文件', async () => {
+      vi.mocked(fs.readdir).mockResolvedValue([
+        { name: 'test.ts', isDirectory: () => false, isFile: () => true },
+        { name: 'test.js', isDirectory: () => false, isFile: () => true },
+      ] as any);
+
+      const result = await searchFilesTool.execute({
+        directory: '.',
+        pattern: '*.ts',
+      });
+
+      expect(result.success).toBe(true);
+      expect(result.output).toContain('test.ts');
+      expect(result.output).not.toContain('test.js');
+    });
+
+    it('没有匹配时返回提示', async () => {
+      vi.mocked(fs.readdir).mockResolvedValue([
+        { name: 'test.js', isDirectory: () => false, isFile: () => true },
+      ] as any);
+
+      const result = await searchFilesTool.execute({
+        directory: '.',
+        pattern: '*.tsx',
+      });
+
+      expect(result.success).toBe(true);
+      expect(result.output).toContain('没有找到匹配的文件');
+    });
+
+    it('递归搜索子目录', async () => {
+      vi.mocked(fs.readdir)
+        .mockResolvedValueOnce([
+          { name: 'src', isDirectory: () => true, isFile: () => false },
+          { name: 'index.ts', isDirectory: () => false, isFile: () => true },
+        ] as any)
+        .mockResolvedValueOnce([
+          { name: 'app.ts', isDirectory: () => false, isFile: () => true },
+        ] as any);
+
+      const result = await searchFilesTool.execute({
+        directory: '.',
+        pattern: '*.ts',
+      });
+
+      expect(result.success).toBe(true);
+      expect(result.output).toContain('index.ts');
+      expect(result.output).toContain('app.ts');
+    });
+
+    it('跳过隐藏文件和 node_modules', async () => {
+      // 第一次调用返回根目录内容，第二次调用返回 src 目录内容
+      vi.mocked(fs.readdir)
+        .mockResolvedValueOnce([
+          { name: '.git', isDirectory: () => true, isFile: () => false },
+          { name: 'node_modules', isDirectory: () => true, isFile: () => false },
+          { name: 'src', isDirectory: () => true, isFile: () => false },
+        ] as any)
+        .mockResolvedValueOnce([
+          { name: 'index.ts', isDirectory: () => false, isFile: () => true },
+        ] as any);
+
+      await searchFilesTool.execute({
+        directory: '.',
+        pattern: '*',
+      });
+
+      // 不应该进入隐藏目录或 node_modules，只进入 src
+      expect(fs.readdir).toHaveBeenCalledTimes(2); // 根目录 + src
+    });
+
+    it('权限被拒绝时返回错误', async () => {
+      vi.mocked(getPermissionManager).mockReturnValue({
+        checkFilePermission: vi.fn().mockResolvedValue({
+          allowed: false,
+          action: 'deny',
+          reason: '不允许搜索',
+        }),
+      } as any);
+
+      const result = await searchFilesTool.execute({
+        directory: '/protected',
+        pattern: '*',
+      });
+
+      expect(result.success).toBe(false);
+      expect(result.error).toContain('权限被拒绝');
+    });
+
+    it('需要确认时返回提示', async () => {
+      vi.mocked(getPermissionManager).mockReturnValue({
+        checkFilePermission: vi.fn().mockResolvedValue({
+          allowed: false,
+          action: 'ask',
+          needsConfirmation: true,
+        }),
+      } as any);
+
+      const result = await searchFilesTool.execute({
+        directory: '.',
+        pattern: '*',
+      });
+
+      expect(result.success).toBe(false);
+      expect(result.error).toContain('需要用户确认');
+    });
+
+    it('支持 glob 模式匹配', async () => {
+      // 恢复权限检查
+      vi.mocked(getPermissionManager).mockReturnValue({
+        checkFilePermission: vi.fn().mockResolvedValue({ allowed: true }),
+      } as any);
+      vi.mocked(fs.readdir).mockResolvedValue([
+        { name: 'component.tsx', isDirectory: () => false, isFile: () => true },
+        { name: 'helper.ts', isDirectory: () => false, isFile: () => true },
+        { name: 'style.css', isDirectory: () => false, isFile: () => true },
+      ] as any);
+
+      // *.tsx 模式会匹配 component.tsx
+      const result = await searchFilesTool.execute({
+        directory: '.',
+        pattern: '*.tsx',
+      });
+
+      expect(result.success).toBe(true);
+      expect(result.output).toContain('component.tsx');
+      expect(result.output).not.toContain('style.css');
+    });
+
+    it('传递正确参数给权限检查', async () => {
+      const mockCheck = vi.fn().mockResolvedValue({ allowed: true });
+      vi.mocked(getPermissionManager).mockReturnValue({
+        checkFilePermission: mockCheck,
+      } as any);
+      vi.mocked(fs.readdir).mockResolvedValue([]);
+
+      await searchFilesTool.execute({
+        directory: 'src',
+        pattern: '*.ts',
+      });
+
+      expect(mockCheck).toHaveBeenCalledWith(
+        expect.objectContaining({
+          operation: 'search',
+        })
+      );
+    });
+  });
+});