refactor: 将 DTO 文件从 internal/model 移动到 internal/model/dto 目录

- 移动 17 个 DTO 文件到 internal/model/dto/ 目录
- 更新所有 DTO 文件的 package 声明从 model 改为 dto
- 更新所有引用文件的 import 和类型引用
  - Handler 层：admin 和 h5 所有处理器
  - Service 层：所有业务服务
  - Routes 层：所有路由定义
  - Tests 层：单元测试和集成测试
- 清理未使用的 import 语句
- 验证：项目构建成功，测试编译通过，LSP 无错误

internal/service/auth/service.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 
 	"github.com/break/junhong_cmp_fiber/internal/model"
+	"github.com/break/junhong_cmp_fiber/internal/model/dto"
 	"github.com/break/junhong_cmp_fiber/internal/store/postgres"
 	"github.com/break/junhong_cmp_fiber/pkg/auth"
 	"github.com/break/junhong_cmp_fiber/pkg/constants"
@@ -42,7 +43,7 @@ func New(
 	}
 }
 
-func (s *Service) Login(ctx context.Context, req *model.LoginRequest, clientIP string) (*model.LoginResponse, error) {
+func (s *Service) Login(ctx context.Context, req *dto.LoginRequest, clientIP string) (*dto.LoginResponse, error) {
 	ctx = pkgGorm.SkipDataPermission(ctx)
 
 	account, err := s.accountStore.GetByUsernameOrPhone(ctx, req.Username)
@@ -107,7 +108,7 @@ func (s *Service) Login(ctx context.Context, req *model.LoginRequest, clientIP s
 		zap.String("ip", clientIP),
 	)
 
-	return &model.LoginResponse{
+	return &dto.LoginResponse{
 		AccessToken:  accessToken,
 		RefreshToken: refreshToken,
 		ExpiresIn:    int64(constants.DefaultAccessTokenTTL.Seconds()),
@@ -134,7 +135,7 @@ func (s *Service) RefreshToken(ctx context.Context, refreshToken string) (string
 	return s.tokenManager.RefreshAccessToken(ctx, refreshToken)
 }
 
-func (s *Service) GetCurrentUser(ctx context.Context, userID uint) (*model.UserInfo, []string, error) {
+func (s *Service) GetCurrentUser(ctx context.Context, userID uint) (*dto.UserInfo, []string, error) {
 	account, err := s.accountStore.GetByID(ctx, userID)
 	if err != nil {
 		if err == gorm.ErrRecordNotFound {
@@ -222,7 +223,7 @@ func (s *Service) getUserPermissions(ctx context.Context, userID uint) ([]string
 	return permCodes, nil
 }
 
-func (s *Service) buildUserInfo(account *model.Account) model.UserInfo {
+func (s *Service) buildUserInfo(account *model.Account) dto.UserInfo {
 	userTypeName := s.getUserTypeName(account.UserType)
 
 	var shopID, enterpriseID uint
@@ -233,7 +234,7 @@ func (s *Service) buildUserInfo(account *model.Account) model.UserInfo {
 		enterpriseID = *account.EnterpriseID
 	}
 
-	return model.UserInfo{
+	return dto.UserInfo{
 		ID:           account.ID,
 		Username:     account.Username,
 		Phone:        account.Phone,