feat(channels): add Shangwutong connector

backend/internal/handler/widget/widget_handler.go

@@ -1485,6 +1485,7 @@ func publicContactPayload(contactInbox *model.ContactInbox, contact *model.Conta
 func (h *WidgetHandler) publicConversationPayload(ctx context.Context, conversation model.Conversation, messages []model.Message) gin.H {
 	payload := gin.H{
 		"id":                   publicDisplayID(conversation),
+		"internal_id":          conversation.ID,
 		"uuid":                 conversation.UUID,
 		"inbox_id":             conversation.InboxID,
 		"contact_last_seen_at": publicUnix(conversation.ContactLastSeenAt),