refactor(auth): 重构认证模块架构 - 将Gateway层组件从Business层分离

范围：src/gateway/auth/, src/business/auth/, src/app.module.ts
涉及文件：
- 新增：src/gateway/auth/ 目录及所有文件
- 移动：Controller、Guard、Decorator、DTO从business层移至gateway层
- 修改：src/business/auth/index.ts（移除Gateway层组件导出）
- 修改：src/app.module.ts（使用AuthGatewayModule替代AuthModule）

主要改进：
- 明确Gateway层和Business层的职责边界
- Controller、Guard、Decorator属于Gateway层职责
- Business层专注于业务逻辑和服务
- 符合分层架构设计原则

src/gateway/auth/jwt_auth.guard.spec.ts

@@ -0,0 +1,164 @@
+/**
+ * JwtAuthGuard 单元测试
+ * 
+ * 功能描述：
+ * - 测试JWT认证守卫的令牌验证功能
+ * - 验证用户信息提取和注入
+ * - 测试认证失败的异常处理
+ * 
+ * 最近修改：
+ * - 2026-01-14: 架构重构 - 从business层移动到gateway层 (修改者: moyin)
+ * - 2026-01-12: 代码规范优化 - 创建缺失的守卫测试文件 (修改者: moyin)
+ * 
+ * @author moyin
+ * @version 1.1.0
+ * @since 2026-01-12
+ * @lastModified 2026-01-14
+ */
+
+import { Test, TestingModule } from '@nestjs/testing';
+import { ExecutionContext, UnauthorizedException } from '@nestjs/common';
+import { JwtAuthGuard } from './jwt_auth.guard';
+import { LoginCoreService } from '../../core/login_core/login_core.service';
+
+describe('JwtAuthGuard', () => {
+  let guard: JwtAuthGuard;
+  let loginCoreService: jest.Mocked<LoginCoreService>;
+  let mockExecutionContext: jest.Mocked<ExecutionContext>;
+  let mockRequest: any;
+
+  beforeEach(async () => {
+    const mockLoginCoreService = {
+      verifyToken: jest.fn(),
+    };
+
+    const module: TestingModule = await Test.createTestingModule({
+      providers: [
+        JwtAuthGuard,
+        {
+          provide: LoginCoreService,
+          useValue: mockLoginCoreService,
+        },
+      ],
+    }).compile();
+
+    guard = module.get<JwtAuthGuard>(JwtAuthGuard);
+    loginCoreService = module.get(LoginCoreService);
+
+    // Mock request object
+    mockRequest = {
+      headers: {},
+      user: undefined,
+    };
+
+    // Mock execution context
+    mockExecutionContext = {
+      switchToHttp: jest.fn().mockReturnValue({
+        getRequest: jest.fn().mockReturnValue(mockRequest),
+      }),
+    } as any;
+  });
+
+  it('should be defined', () => {
+    expect(guard).toBeDefined();
+  });
+
+  describe('canActivate', () => {
+    it('should allow access with valid JWT token', async () => {
+      const mockPayload = {
+        sub: '1',
+        username: 'testuser',
+        role: 1,
+        type: 'access' as const,
+        iat: Math.floor(Date.now() / 1000),
+        exp: Math.floor(Date.now() / 1000) + 3600,
+      };
+
+      mockRequest.headers.authorization = 'Bearer valid_jwt_token';
+      loginCoreService.verifyToken.mockResolvedValue(mockPayload);
+
+      const result = await guard.canActivate(mockExecutionContext);
+
+      expect(result).toBe(true);
+      expect(mockRequest.user).toEqual(mockPayload);
+      expect(loginCoreService.verifyToken).toHaveBeenCalledWith('valid_jwt_token', 'access');
+    });
+
+    it('should deny access when authorization header is missing', async () => {
+      mockRequest.headers.authorization = undefined;
+
+      await expect(guard.canActivate(mockExecutionContext))
+        .rejects.toThrow(UnauthorizedException);
+      
+      expect(loginCoreService.verifyToken).not.toHaveBeenCalled();
+    });
+
+    it('should deny access when token format is invalid', async () => {
+      mockRequest.headers.authorization = 'InvalidFormat token';
+
+      await expect(guard.canActivate(mockExecutionContext))
+        .rejects.toThrow(UnauthorizedException);
+      
+      expect(loginCoreService.verifyToken).not.toHaveBeenCalled();
+    });
+
+    it('should deny access when token is not Bearer type', async () => {
+      mockRequest.headers.authorization = 'Basic dXNlcjpwYXNz';
+
+      await expect(guard.canActivate(mockExecutionContext))
+        .rejects.toThrow(UnauthorizedException);
+      
+      expect(loginCoreService.verifyToken).not.toHaveBeenCalled();
+    });
+
+    it('should deny access when JWT token verification fails', async () => {
+      mockRequest.headers.authorization = 'Bearer invalid_jwt_token';
+      loginCoreService.verifyToken.mockRejectedValue(new Error('Token expired'));
+
+      await expect(guard.canActivate(mockExecutionContext))
+        .rejects.toThrow(UnauthorizedException);
+      
+      expect(loginCoreService.verifyToken).toHaveBeenCalledWith('invalid_jwt_token', 'access');
+    });
+
+    it('should extract token correctly from Authorization header', async () => {
+      const mockPayload = {
+        sub: '1',
+        username: 'testuser',
+        role: 1,
+        type: 'access' as const,
+        iat: Math.floor(Date.now() / 1000),
+        exp: Math.floor(Date.now() / 1000) + 3600,
+      };
+
+      mockRequest.headers.authorization = 'Bearer eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.test.token';
+      loginCoreService.verifyToken.mockResolvedValue(mockPayload);
+
+      const result = await guard.canActivate(mockExecutionContext);
+
+      expect(result).toBe(true);
+      expect(loginCoreService.verifyToken).toHaveBeenCalledWith(
+        'eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.test.token',
+        'access'
+      );
+    });
+
+    it('should handle empty token after Bearer', async () => {
+      mockRequest.headers.authorization = 'Bearer ';
+
+      await expect(guard.canActivate(mockExecutionContext))
+        .rejects.toThrow(UnauthorizedException);
+      
+      expect(loginCoreService.verifyToken).not.toHaveBeenCalled();
+    });
+
+    it('should handle authorization header with only Bearer', async () => {
+      mockRequest.headers.authorization = 'Bearer';
+
+      await expect(guard.canActivate(mockExecutionContext))
+        .rejects.toThrow(UnauthorizedException);
+      
+      expect(loginCoreService.verifyToken).not.toHaveBeenCalled();
+    });
+  });
+});