feat: 实现运营商模块重构，添加冗余字段优化查询性能

主要变更：
- 新增 Carrier CRUD API（创建、列表、详情、更新、删除、状态更新）
- IotCard/IotCardImportTask 添加 carrier_type/carrier_name 冗余字段
- 移除 Carrier 表的 channel_name/channel_code 字段
- 查询时直接使用冗余字段，避免 JOIN Carrier 表
- 添加数据库迁移脚本（000021-000023）
- 添加单元测试和集成测试
- 同步更新 OpenAPI 文档和 specs

internal/model/dto/carrier_dto.go

@@ -0,0 +1,54 @@
+package dto
+
+type CreateCarrierRequest struct {
+	CarrierCode string `json:"carrier_code" validate:"required,min=1,max=50" required:"true" minLength:"1" maxLength:"50" description:"运营商编码"`
+	CarrierName string `json:"carrier_name" validate:"required,min=1,max=100" required:"true" minLength:"1" maxLength:"100" description:"运营商名称"`
+	CarrierType string `json:"carrier_type" validate:"required,oneof=CMCC CUCC CTCC CBN" required:"true" description:"运营商类型 (CMCC:中国移动, CUCC:中国联通, CTCC:中国电信, CBN:中国广电)"`
+	Description string `json:"description" validate:"omitempty,max=500" maxLength:"500" description:"运营商描述"`
+}
+
+type UpdateCarrierRequest struct {
+	CarrierName *string `json:"carrier_name" validate:"omitempty,min=1,max=100" minLength:"1" maxLength:"100" description:"运营商名称"`
+	Description *string `json:"description" validate:"omitempty,max=500" maxLength:"500" description:"运营商描述"`
+}
+
+type CarrierListRequest struct {
+	Page        int     `json:"page" query:"page" validate:"omitempty,min=1" minimum:"1" description:"页码"`
+	PageSize    int     `json:"page_size" query:"page_size" validate:"omitempty,min=1,max=100" minimum:"1" maximum:"100" description:"每页数量"`
+	CarrierType *string `json:"carrier_type" query:"carrier_type" validate:"omitempty,oneof=CMCC CUCC CTCC CBN" description:"运营商类型 (CMCC:中国移动, CUCC:中国联通, CTCC:中国电信, CBN:中国广电)"`
+	CarrierName *string `json:"carrier_name" query:"carrier_name" validate:"omitempty,max=100" maxLength:"100" description:"运营商名称（模糊搜索）"`
+	Status      *int    `json:"status" query:"status" validate:"omitempty,oneof=0 1" description:"状态 (1:启用, 0:禁用)"`
+}
+
+type UpdateCarrierStatusRequest struct {
+	Status int `json:"status" validate:"required,oneof=0 1" required:"true" description:"状态 (1:启用, 0:禁用)"`
+}
+
+type CarrierResponse struct {
+	ID          uint   `json:"id" description:"运营商ID"`
+	CarrierCode string `json:"carrier_code" description:"运营商编码"`
+	CarrierName string `json:"carrier_name" description:"运营商名称"`
+	CarrierType string `json:"carrier_type" description:"运营商类型 (CMCC:中国移动, CUCC:中国联通, CTCC:中国电信, CBN:中国广电)"`
+	Description string `json:"description" description:"运营商描述"`
+	Status      int    `json:"status" description:"状态 (1:启用, 0:禁用)"`
+	CreatedAt   string `json:"created_at" description:"创建时间"`
+	UpdatedAt   string `json:"updated_at" description:"更新时间"`
+}
+
+type UpdateCarrierParams struct {
+	IDReq
+	UpdateCarrierRequest
+}
+
+type UpdateCarrierStatusParams struct {
+	IDReq
+	UpdateCarrierStatusRequest
+}
+
+type CarrierPageResult struct {
+	List       []*CarrierResponse `json:"list" description:"运营商列表"`
+	Total      int64              `json:"total" description:"总数"`
+	Page       int                `json:"page" description:"当前页"`
+	PageSize   int                `json:"page_size" description:"每页数量"`
+	TotalPages int                `json:"total_pages" description:"总页数"`
+}