fix(01-05): 设备导入补充 IMEI 字段（CRITICAL-07）

- DeviceRow struct 新增 IMEI string 字段
- buildDeviceColumnIndex 支持 imei/设备imei/imei号 列名映射
- ParseDeviceExcel 解析数据行时填充 row.IMEI
- device_import.go processBatch 创建 model.Device 时赋值 IMEI: row.IMEI

internal/task/device_import.go

@@ -264,6 +264,7 @@ func (h *DeviceImportHandler) processBatch(ctx context.Context, task *model.Devi
 
 			device := &model.Device{
 				VirtualNo:    row.VirtualNo,
+				IMEI:         row.IMEI,
 				DeviceName:   row.DeviceName,
 				DeviceModel:  row.DeviceModel,
 				DeviceType:   row.DeviceType,

pkg/utils/excel.go

@@ -35,6 +35,7 @@ type CSVParseError struct {
 type DeviceRow struct {
 	Line         int
 	VirtualNo    string
+	IMEI         string // 设备IMEI，对应 Excel IMEI 列，用于 Gateway API 调用
 	DeviceName   string
 	DeviceModel  string
 	DeviceType   string
@@ -132,6 +133,9 @@ func ParseDeviceExcel(filePath string) ([]DeviceRow, int, error) {
 		if idx := colIndex["virtual_no"]; idx >= 0 && idx < len(record) {
 			row.VirtualNo = strings.TrimSpace(record[idx])
 		}
+		if idx := colIndex["imei"]; idx >= 0 && idx < len(record) {
+			row.IMEI = strings.TrimSpace(record[idx])
+		}
 		if idx := colIndex["device_name"]; idx >= 0 && idx < len(record) {
 			row.DeviceName = strings.TrimSpace(record[idx])
 		}
@@ -317,9 +321,11 @@ func findCardColumns(header []string) (iccidCol, msisdnCol, virtualNoCol int) {
 
 // buildDeviceColumnIndex 构建设备导入列索引
 // 识别表头中的列名,返回列名到列索引的映射
+// IMEI 列支持多种列名格式：imei/IMEI/设备IMEI/IMEI号
 func buildDeviceColumnIndex(header []string) map[string]int {
 	index := map[string]int{
 		"virtual_no":    -1,
+		"imei":          -1,
 		"device_name":   -1,
 		"device_model":  -1,
 		"device_type":   -1,
@@ -332,9 +338,17 @@ func buildDeviceColumnIndex(header []string) map[string]int {
 	}
 
 	for i, col := range header {
-		col = strings.ToLower(strings.TrimSpace(col))
-		if _, exists := index[col]; exists {
-			index[col] = i
+		normalized := strings.ToLower(strings.TrimSpace(col))
+		// 支持 IMEI 多种列名格式
+		switch normalized {
+		case "imei", "设备imei", "imei号":
+			if index["imei"] == -1 {
+				index["imei"] = i
+			}
+		default:
+			if _, exists := index[normalized]; exists {
+				index[normalized] = i
+			}
 		}
 	}