支持后台转移发布所有权

backend/internal/modules/chat/listing_group.go

@@ -22,7 +22,7 @@ var (
 )
 
 // EnsureListingConversation 确保发布群存在(幂等)
-func EnsureListingConversation(tx *gorm.DB, listing model.RentalListing) (*model.ChatConversation, error) {
+func EnsureListingConversation(tx *gorm.DB, listing model.RentalListing, preferredSupportAdminID uint64) (*model.ChatConversation, error) {
 	// 1. 幂等查重
 	var existing model.ChatConversation
 	err := tx.Where("listing_id = ?", listing.ID).First(&existing).Error
@@ -56,8 +56,12 @@ func EnsureListingConversation(tx *gorm.DB, listing model.RentalListing) (*model
 		},
 	}
 
-	// 获取客服
-	if supportID := defaultSupportAdminID(tx); supportID > 0 {
+	// 获取客服。开放上传场景优先拉上传管理员，普通发布回退到默认客服。
+	supportID := preferredSupportAdminID
+	if supportID <= 0 {
+		supportID = defaultSupportAdminID(tx)
+	}
+	if supportID > 0 {
 		participants = append(participants, model.ChatParticipant{
 			ConversationID:  conversation.ID,
 			ParticipantType: "admin",