backfill, msgconv: don't panic when the whatsmeow client is nil

pkg/connector/backfill.go

@@ -602,6 +602,9 @@ func (wa *WhatsAppClient) convertHistorySyncMessages(
 	messages []*waWeb.WebMessageInfo,
 	explodeOnError bool,
 ) (*bridgev2.FetchMessagesResponse, error) {
+	if wa.Client == nil {
+		return nil, bridgev2.ErrNotLoggedIn
+	}
 	oldestTS := messages[len(messages)-1].GetMessageTimestamp()
 	newestTS := messages[0].GetMessageTimestamp()
 	convertedMessages := make([]*bridgev2.BackfillMessage, 0, len(messages))

pkg/msgconv/from-whatsapp.go

@@ -76,7 +76,11 @@ func (mc *MessageConverter) getBasicUserInfo(ctx context.Context, user types.JID
 		pnJID = user
 	} else if user.Server == types.HiddenUserServer {
 		cli := getClient(ctx)
-		if user.User == cli.Store.GetLID().User {
+		if cli == nil {
+			zerolog.Ctx(ctx).Warn().
+				Stringer("lid", user).
+				Msg("Client is nil, cannot resolve LID mention to phone number")
+		} else if user.User == cli.Store.GetLID().User {
 			pnJID = cli.Store.GetJID()
 		} else {
 			pnJID, err = cli.Store.LIDs.GetPNForLID(ctx, user)