refactor: 重构后端架构为 go-zero 框架，优化项目结构

主要变更:
- 采用 go-zero 框架替代 Gin，提升开发效率
- 重构项目结构，API 文件模块化组织
- 将 model 移至 api/internal/model 目录
- 移除 common 包，改为标准 pkg 目录结构
- 实现统一的仓储模式，支持配置驱动数据库切换
- 简化测试策略，专注 API 集成测试
- 更新 CLAUDE.md 文档，提供详细的开发指导

技术栈更新:
- 框架: Gin → go-zero v1.6.0+
- 代码生成: 引入 goctl 工具
- 架构模式: 四层架构 → go-zero 三层架构 (Handler→Logic→Model)
- 项目布局: 遵循 Go 社区标准和 go-zero 最佳实践

backend/internal/service/user_service.go

@@ -3,10 +3,9 @@ package service
 import (
 	"context"
 	"errors"
-	"fmt"
+	"time"
 
-	"photography-backend/internal/models"
-	"photography-backend/internal/utils"
+	"photography-backend/internal/model/entity"
 
 	"go.uber.org/zap"
 	"golang.org/x/crypto/bcrypt"
@@ -36,7 +35,7 @@ type UserListParams struct {
 
 // UserListResponse 用户列表响应
 type UserListResponse struct {
-	Users []models.User `json:"users"`
+	Users []entity.User `json:"users"`
 	Total int64         `json:"total"`
 	Page  int           `json:"page"`
 	Limit int           `json:"limit"`
@@ -78,14 +77,14 @@ func (s *UserService) GetUsers(ctx context.Context, params UserListParams) (*Use
 	// 计算总数
 	var total int64
 	countQuery := query
-	if err := countQuery.Model(&models.User{}).Count(&total).Error; err != nil {
+	if err := countQuery.Model(&entity.User{}).Count(&total).Error; err != nil {
 		s.logger.Error("Failed to count users", zap.Error(err))
 		return nil, err
 	}
 
 	// 分页查询
 	offset := (params.Page - 1) * params.Limit
-	var users []models.User
+	var users []entity.User
 	if err := query.
 		Order("created_at DESC").
 		Offset(offset).
@@ -108,8 +107,8 @@ func (s *UserService) GetUsers(ctx context.Context, params UserListParams) (*Use
 }
 
 // GetUserByID 根据ID获取用户
-func (s *UserService) GetUserByID(ctx context.Context, id uint) (*models.User, error) {
-	var user models.User
+func (s *UserService) GetUserByID(ctx context.Context, id uint) (*entity.User, error) {
+	var user entity.User
 	if err := s.db.WithContext(ctx).First(&user, id).Error; err != nil {
 		if errors.Is(err, gorm.ErrRecordNotFound) {
 			return nil, errors.New("user not found")
@@ -122,8 +121,8 @@ func (s *UserService) GetUserByID(ctx context.Context, id uint) (*models.User, e
 }
 
 // GetUserByUsername 根据用户名获取用户
-func (s *UserService) GetUserByUsername(ctx context.Context, username string) (*models.User, error) {
-	var user models.User
+func (s *UserService) GetUserByUsername(ctx context.Context, username string) (*entity.User, error) {
+	var user entity.User
 	if err := s.db.WithContext(ctx).Where("username = ?", username).First(&user).Error; err != nil {
 		if errors.Is(err, gorm.ErrRecordNotFound) {
 			return nil, errors.New("user not found")
@@ -136,8 +135,8 @@ func (s *UserService) GetUserByUsername(ctx context.Context, username string) (*
 }
 
 // GetUserByEmail 根据邮箱获取用户
-func (s *UserService) GetUserByEmail(ctx context.Context, email string) (*models.User, error) {
-	var user models.User
+func (s *UserService) GetUserByEmail(ctx context.Context, email string) (*entity.User, error) {
+	var user entity.User
 	if err := s.db.WithContext(ctx).Where("email = ?", email).First(&user).Error; err != nil {
 		if errors.Is(err, gorm.ErrRecordNotFound) {
 			return nil, errors.New("user not found")
@@ -150,9 +149,9 @@ func (s *UserService) GetUserByEmail(ctx context.Context, email string) (*models
 }
 
 // CreateUser 创建用户
-func (s *UserService) CreateUser(ctx context.Context, req *models.CreateUserRequest) (*models.User, error) {
+func (s *UserService) CreateUser(ctx context.Context, req *entity.CreateUserRequest) (*entity.User, error) {
 	// 验证用户名唯一性
-	var existingUser models.User
+	var existingUser entity.User
 	if err := s.db.WithContext(ctx).Where("username = ?", req.Username).First(&existingUser).Error; err == nil {
 		return nil, errors.New("username already exists")
 	}
@@ -169,7 +168,7 @@ func (s *UserService) CreateUser(ctx context.Context, req *models.CreateUserRequ
 		return nil, err
 	}
 
-	user := &models.User{
+	user := &entity.User{
 		Username: req.Username,
 		Email:    req.Email,
 		Password: string(hashedPassword),
@@ -187,9 +186,9 @@ func (s *UserService) CreateUser(ctx context.Context, req *models.CreateUserRequ
 }
 
 // UpdateUser 更新用户
-func (s *UserService) UpdateUser(ctx context.Context, id uint, req *models.UpdateUserRequest) (*models.User, error) {
+func (s *UserService) UpdateUser(ctx context.Context, id uint, req *entity.UpdateUserRequest) (*entity.User, error) {
 	// 检查用户是否存在
-	var user models.User
+	var user entity.User
 	if err := s.db.WithContext(ctx).First(&user, id).Error; err != nil {
 		if errors.Is(err, gorm.ErrRecordNotFound) {
 			return nil, errors.New("user not found")
@@ -202,7 +201,7 @@ func (s *UserService) UpdateUser(ctx context.Context, id uint, req *models.Updat
 	
 	if req.Username != nil {
 		// 验证用户名唯一性
-		var existingUser models.User
+		var existingUser entity.User
 		if err := s.db.WithContext(ctx).Where("username = ? AND id != ?", *req.Username, id).First(&existingUser).Error; err == nil {
 			return nil, errors.New("username already exists")
 		}
@@ -211,7 +210,7 @@ func (s *UserService) UpdateUser(ctx context.Context, id uint, req *models.Updat
 	
 	if req.Email != nil {
 		// 验证邮箱唯一性
-		var existingUser models.User
+		var existingUser entity.User
 		if err := s.db.WithContext(ctx).Where("email = ? AND id != ?", *req.Email, id).First(&existingUser).Error; err == nil {
 			return nil, errors.New("email already exists")
 		}
@@ -238,9 +237,9 @@ func (s *UserService) UpdateUser(ctx context.Context, id uint, req *models.Updat
 }
 
 // UpdateCurrentUser 更新当前用户信息
-func (s *UserService) UpdateCurrentUser(ctx context.Context, id uint, req *models.UpdateCurrentUserRequest) (*models.User, error) {
+func (s *UserService) UpdateCurrentUser(ctx context.Context, id uint, req *entity.UpdateCurrentUserRequest) (*entity.User, error) {
 	// 检查用户是否存在
-	var user models.User
+	var user entity.User
 	if err := s.db.WithContext(ctx).First(&user, id).Error; err != nil {
 		if errors.Is(err, gorm.ErrRecordNotFound) {
 			return nil, errors.New("user not found")
@@ -253,7 +252,7 @@ func (s *UserService) UpdateCurrentUser(ctx context.Context, id uint, req *model
 	
 	if req.Username != nil {
 		// 验证用户名唯一性
-		var existingUser models.User
+		var existingUser entity.User
 		if err := s.db.WithContext(ctx).Where("username = ? AND id != ?", *req.Username, id).First(&existingUser).Error; err == nil {
 			return nil, errors.New("username already exists")
 		}
@@ -262,7 +261,7 @@ func (s *UserService) UpdateCurrentUser(ctx context.Context, id uint, req *model
 	
 	if req.Email != nil {
 		// 验证邮箱唯一性
-		var existingUser models.User
+		var existingUser entity.User
 		if err := s.db.WithContext(ctx).Where("email = ? AND id != ?", *req.Email, id).First(&existingUser).Error; err == nil {
 			return nil, errors.New("email already exists")
 		}
@@ -283,7 +282,7 @@ func (s *UserService) UpdateCurrentUser(ctx context.Context, id uint, req *model
 // DeleteUser 删除用户
 func (s *UserService) DeleteUser(ctx context.Context, id uint) error {
 	// 检查用户是否存在
-	var user models.User
+	var user entity.User
 	if err := s.db.WithContext(ctx).First(&user, id).Error; err != nil {
 		if errors.Is(err, gorm.ErrRecordNotFound) {
 			return errors.New("user not found")
@@ -302,9 +301,9 @@ func (s *UserService) DeleteUser(ctx context.Context, id uint) error {
 }
 
 // ChangePassword 修改密码
-func (s *UserService) ChangePassword(ctx context.Context, id uint, req *models.ChangePasswordRequest) error {
+func (s *UserService) ChangePassword(ctx context.Context, id uint, req *entity.ChangePasswordRequest) error {
 	// 检查用户是否存在
-	var user models.User
+	var user entity.User
 	if err := s.db.WithContext(ctx).First(&user, id).Error; err != nil {
 		if errors.Is(err, gorm.ErrRecordNotFound) {
 			return errors.New("user not found")
@@ -335,8 +334,8 @@ func (s *UserService) ChangePassword(ctx context.Context, id uint, req *models.C
 }
 
 // ValidateCredentials 验证用户凭据
-func (s *UserService) ValidateCredentials(ctx context.Context, username, password string) (*models.User, error) {
-	var user models.User
+func (s *UserService) ValidateCredentials(ctx context.Context, username, password string) (*entity.User, error) {
+	var user entity.User
 	
 	// 根据用户名或邮箱查找用户
 	if err := s.db.WithContext(ctx).Where("username = ? OR email = ?", username, username).First(&user).Error; err != nil {
@@ -361,16 +360,16 @@ func (s *UserService) ValidateCredentials(ctx context.Context, username, passwor
 }
 
 // GetUserStats 获取用户统计信息
-func (s *UserService) GetUserStats(ctx context.Context) (*models.UserStats, error) {
-	var stats models.UserStats
+func (s *UserService) GetUserStats(ctx context.Context) (*entity.UserStats, error) {
+	var stats entity.UserStats
 
 	// 总用户数
-	if err := s.db.WithContext(ctx).Model(&models.User{}).Count(&stats.Total).Error; err != nil {
+	if err := s.db.WithContext(ctx).Model(&entity.User{}).Count(&stats.Total).Error; err != nil {
 		return nil, err
 	}
 
 	// 活跃用户数
-	if err := s.db.WithContext(ctx).Model(&models.User{}).
+	if err := s.db.WithContext(ctx).Model(&entity.User{}).
 		Where("is_active = ?", true).Count(&stats.Active).Error; err != nil {
 		return nil, err
 	}
@@ -380,7 +379,7 @@ func (s *UserService) GetUserStats(ctx context.Context) (*models.UserStats, erro
 		Role  string `json:"role"`
 		Count int64  `json:"count"`
 	}
-	if err := s.db.WithContext(ctx).Model(&models.User{}).
+	if err := s.db.WithContext(ctx).Model(&entity.User{}).
 		Select("role, COUNT(*) as count").
 		Where("is_active = ?", true).
 		Group("role").
@@ -395,7 +394,7 @@ func (s *UserService) GetUserStats(ctx context.Context) (*models.UserStats, erro
 
 	// 本月新增用户
 	startOfMonth := time.Now().AddDate(0, 0, -time.Now().Day()+1)
-	if err := s.db.WithContext(ctx).Model(&models.User{}).
+	if err := s.db.WithContext(ctx).Model(&entity.User{}).
 		Where("created_at >= ?", startOfMonth).
 		Count(&stats.ThisMonth).Error; err != nil {
 		return nil, err
@@ -403,7 +402,7 @@ func (s *UserService) GetUserStats(ctx context.Context) (*models.UserStats, erro
 
 	// 今日新增用户
 	startOfDay := time.Now().Truncate(24 * time.Hour)
-	if err := s.db.WithContext(ctx).Model(&models.User{}).
+	if err := s.db.WithContext(ctx).Model(&entity.User{}).
 		Where("created_at >= ?", startOfDay).
 		Count(&stats.Today).Error; err != nil {
 		return nil, err
@@ -415,7 +414,7 @@ func (s *UserService) GetUserStats(ctx context.Context) (*models.UserStats, erro
 // IsUsernameAvailable 检查用户名是否可用
 func (s *UserService) IsUsernameAvailable(ctx context.Context, username string) (bool, error) {
 	var count int64
-	if err := s.db.WithContext(ctx).Model(&models.User{}).
+	if err := s.db.WithContext(ctx).Model(&entity.User{}).
 		Where("username = ?", username).Count(&count).Error; err != nil {
 		return false, err
 	}
@@ -425,7 +424,7 @@ func (s *UserService) IsUsernameAvailable(ctx context.Context, username string)
 // IsEmailAvailable 检查邮箱是否可用
 func (s *UserService) IsEmailAvailable(ctx context.Context, email string) (bool, error) {
 	var count int64
-	if err := s.db.WithContext(ctx).Model(&models.User{}).
+	if err := s.db.WithContext(ctx).Model(&entity.User{}).
 		Where("email = ?", email).Count(&count).Error; err != nil {
 		return false, err
 	}