message: Fix exception on std::stoi with empty string (lib)
  Closes
diff: @@ -6315,9 +6315,14 @@ void Context::syncTranslateGUIDToLocalID(Json::Value &item) {
  template<typename T>
  error Context::syncHandleResponse(Json::Value &array, const std::vector<T*> &source) {
  // this only looks into the container of modified items, not the whole RelatedData container
  - auto findByLocalID = [](auto &source, auto localID) -> typename std::remove_reference<decltype(source)>::type::value_type {
  - auto id = stoi(localID);
  + auto findByLocalID = [](auto &source, std::string &&localID) -> typename std::remove_reference<decltype(source)>::type::value_type {
  + int64_t id = 0;
  + try {
  + id = stoi(localID);
  id = id < 0 ? -id : id;
  + } catch (...) {
  + return nullptr;
  + }
  for (auto i : source) {
  if (i->LocalID() == id) {
  return i;
  