fix: add auto join for messages

Author: gsanchietti

service/messages.go

@@ -78,6 +78,13 @@ func (s *MessageService) SendMessage(ctx context.Context, req *models.SendMessag
 
 	logger.Debug().Str("user_id", string(userID)).Str("room_id", string(roomID)).Msg("sending message to room")
 
+	// Ensure the sender is a member of the room
+	_, err = s.matrixClient.JoinRoom(ctx, userID, roomID)
+	if err != nil {
+		logger.Error().Str("user_id", string(userID)).Str("room_id", string(roomID)).Err(err).Msg("failed to join room")
+		return nil, fmt.Errorf("send message: %w", err)
+	}
+
 	content := &event.MessageEventContent{
 		MsgType: event.MsgText,
 		Body:    req.SMSBody,
@@ -326,7 +333,7 @@ func mapAuthErr(err error) error {
 	if errors.Is(err, ErrAuthentication) {
 		return err
 	}
-	if errors.Is(err, mautrix.MUnknownToken) || errors.Is(err, mautrix.MMissingToken) || errors.Is(err, mautrix.MForbidden) {
+	if errors.Is(err, mautrix.MUnknownToken) || errors.Is(err, mautrix.MMissingToken) {
 		return fmt.Errorf("%w", ErrAuthentication)
 	}
 	return err