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

tests/unit/shop_service_test.go

@@ -8,6 +8,7 @@ import (
 	"github.com/stretchr/testify/require"
 
 	"github.com/break/junhong_cmp_fiber/internal/model"
+	"github.com/break/junhong_cmp_fiber/internal/model/dto"
 	"github.com/break/junhong_cmp_fiber/internal/service/shop"
 	"github.com/break/junhong_cmp_fiber/internal/store/postgres"
 	"github.com/break/junhong_cmp_fiber/pkg/constants"
@@ -26,7 +27,7 @@ func TestShopService_Create(t *testing.T) {
 
 	t.Run("创建一级店铺成功", func(t *testing.T) {
 		ctx := createContextWithUserID(1)
-		req := &model.CreateShopRequest{
+		req := &dto.CreateShopRequest{
 			ShopName:     "测试一级店铺",
 			ShopCode:     "SHOP_L1_001",
 			ParentID:     nil,
@@ -71,7 +72,7 @@ func TestShopService_Create(t *testing.T) {
 		require.NoError(t, err)
 
 		// 创建二级店铺
-		req := &model.CreateShopRequest{
+		req := &dto.CreateShopRequest{
 			ShopName:     "测试二级店铺",
 			ShopCode:     "SHOP_L2_001",
 			ParentID:     &parent.ID,
@@ -123,7 +124,7 @@ func TestShopService_Create(t *testing.T) {
 		assert.Equal(t, 7, shops[6].Level)
 
 		// 尝试创建第 8 级店铺（应该失败）
-		req := &model.CreateShopRequest{
+		req := &dto.CreateShopRequest{
 			ShopName:     "第8级店铺",
 			ShopCode:     "SHOP_L8_001",
 			ParentID:     &shops[6].ID, // 第7级店铺的ID
@@ -149,7 +150,7 @@ func TestShopService_Create(t *testing.T) {
 		ctx := createContextWithUserID(1)
 
 		// 创建第一个店铺
-		req1 := &model.CreateShopRequest{
+		req1 := &dto.CreateShopRequest{
 			ShopName:     "店铺A",
 			ShopCode:     "UNIQUE_CODE_001",
 			ContactName:  "张三",
@@ -162,7 +163,7 @@ func TestShopService_Create(t *testing.T) {
 		require.NoError(t, err)
 
 		// 尝试创建相同编号的店铺（应该失败）
-		req2 := &model.CreateShopRequest{
+		req2 := &dto.CreateShopRequest{
 			ShopName:     "店铺B",
 			ShopCode:     "UNIQUE_CODE_001", // 重复编号
 			ContactName:  "李四",
@@ -186,7 +187,7 @@ func TestShopService_Create(t *testing.T) {
 		ctx := createContextWithUserID(1)
 
 		nonExistentID := uint(99999)
-		req := &model.CreateShopRequest{
+		req := &dto.CreateShopRequest{
 			ShopName:     "测试店铺",
 			ShopCode:     "SHOP_INVALID_PARENT",
 			ParentID:     &nonExistentID, // 不存在的上级店铺 ID
@@ -211,7 +212,7 @@ func TestShopService_Create(t *testing.T) {
 	t.Run("未授权访问应失败", func(t *testing.T) {
 		ctx := context.Background() // 没有用户 ID 的 context
 
-		req := &model.CreateShopRequest{
+		req := &dto.CreateShopRequest{
 			ShopName:     "测试店铺",
 			ShopCode:     "SHOP_UNAUTHORIZED",
 			ContactName:  "测试",
@@ -262,7 +263,7 @@ func TestShopService_Update(t *testing.T) {
 		require.NoError(t, err)
 
 		// 更新店铺
-		req := &model.UpdateShopRequest{
+		req := &dto.UpdateShopRequest{
 			ShopName:     "更新后的店铺名称",
 			ContactName:  "新联系人",
 			ContactPhone: "13900000001",
@@ -316,7 +317,7 @@ func TestShopService_Update(t *testing.T) {
 		require.NoError(t, err)
 
 		// 尝试更新 shop2 的名称为已存在的名称（应该成功，因为名称不需要唯一性）
-		req := &model.UpdateShopRequest{
+		req := &dto.UpdateShopRequest{
 			ShopName: "店铺1",
 			Status:   constants.StatusEnabled,
 		}
@@ -330,7 +331,7 @@ func TestShopService_Update(t *testing.T) {
 	t.Run("更新不存在的店铺应失败", func(t *testing.T) {
 		ctx := createContextWithUserID(1)
 
-		req := &model.UpdateShopRequest{
+		req := &dto.UpdateShopRequest{
 			ShopName: "新名称",
 			Status:   constants.StatusEnabled,
 		}
@@ -347,7 +348,7 @@ func TestShopService_Update(t *testing.T) {
 	t.Run("未授权访问应失败", func(t *testing.T) {
 		ctx := context.Background()
 
-		req := &model.UpdateShopRequest{
+		req := &dto.UpdateShopRequest{
 			ShopName: "新名称",
 			Status:   constants.StatusEnabled,
 		}