forked from loafle/openapi-generator-original
* [C++][Pistache] fix Wconversion warning * [C++][Pistache] fix struct model compilation with std::optional * [C++][Pistache] Add validation to struct model
* [C++][Pistache] fix Wconversion warning * [C++][Pistache] fix struct model compilation with std::optional * [C++][Pistache] Add validation to struct model