fix(backend): JWT config mapstructure tag 修复 + 模型从 hotel 重构为 shop

- 修复 JWTConfig 缺少 mapstructure tag 导致 access_expire_min 解析为 0，
  token 签发即过期，所有 API 请求返回 401
- 全部 config struct 补齐 mapstructure tag（secret/dsn/hmac_secret 等）
- 模型层从 hotel/HotelID 统一重命名为 shop/ShopID
- 删除旧 migrations（001-004），新增 001_init 综合迁移文件
- 更新 schema.sql、testutil、handler/service/model 相关引用

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

backend/internal/handler/warehouse.go

@@ -19,43 +19,43 @@ func NewWarehouseHandler(db *gorm.DB) *WarehouseHandler {
 }
 
 func (h *WarehouseHandler) List(c *gin.Context) {
-	hotelID := middleware.GetHotelID(c)
+	shopID := middleware.GetShopID(c)
 	var warehouses []model.Warehouse
-	h.db.Where("hotel_id = ? AND deleted_at IS NULL", hotelID).Find(&warehouses)
+	h.db.Where("shop_id = ? AND deleted_at IS NULL", shopID).Find(&warehouses)
 	c.JSON(http.StatusOK, gin.H{"data": warehouses})
 }
 
 func (h *WarehouseHandler) Create(c *gin.Context) {
-	hotelID := middleware.GetHotelID(c)
+	shopID := middleware.GetShopID(c)
 	var w model.Warehouse
 	if err := c.ShouldBindJSON(&w); err != nil {
 		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
 		return
 	}
-	w.HotelID = hotelID
+	w.ShopID = shopID
 	h.db.Create(&w)
 	c.JSON(http.StatusCreated, gin.H{"data": w})
 }
 
 func (h *WarehouseHandler) Update(c *gin.Context) {
-	hotelID := middleware.GetHotelID(c)
+	shopID := middleware.GetShopID(c)
 	var w model.Warehouse
-	if err := h.db.Where("id = ? AND hotel_id = ? AND deleted_at IS NULL", c.Param("id"), hotelID).
+	if err := h.db.Where("id = ? AND shop_id = ? AND deleted_at IS NULL", c.Param("id"), shopID).
 		First(&w).Error; err != nil {
 		c.JSON(http.StatusNotFound, gin.H{"error": "not found"})
 		return
 	}
 	c.ShouldBindJSON(&w)
-	w.HotelID = hotelID
+	w.ShopID = shopID
 	h.db.Save(&w)
 	c.JSON(http.StatusOK, gin.H{"data": w})
 }
 
 func (h *WarehouseHandler) Delete(c *gin.Context) {
-	hotelID := middleware.GetHotelID(c)
+	shopID := middleware.GetShopID(c)
 	now := timeNow()
 	h.db.Model(&model.Warehouse{}).
-		Where("id = ? AND hotel_id = ? AND deleted_at IS NULL", c.Param("id"), hotelID).
+		Where("id = ? AND shop_id = ? AND deleted_at IS NULL", c.Param("id"), shopID).
 		Update("deleted_at", now)
 	c.JSON(http.StatusOK, gin.H{"message": "deleted"})
 }