统一时间格式和时区

backend/internal/service/delivery.go

@@ -16,6 +16,7 @@ import (
 	"time"
 
 	"affiliate_dash/internal/model"
+	"affiliate_dash/internal/pkg/timeutil"
 
 	"gorm.io/gorm"
 	"gorm.io/gorm/clause"
@@ -349,7 +350,7 @@ func (s *DeliveryService) claimDeliverySubmission(merchantID, apiClientID uint,
 		}
 		raw, _ := json.Marshal(map[string]interface{}{
 			"source":               "delivery_proxy",
-			"submit_started_at":    time.Now().UTC().Format(time.RFC3339),
+			"submit_started_at":    timeutil.FormatAPITime(time.Now()),
 			"provider_order_stage": "claimed",
 		})
 		if err := tx.Model(&order).Updates(map[string]interface{}{