Boost.Nowide iostream initialization and console buffer correctness

Boost.Nowide iostream initialization and console buffer correctness: a task in LegoFlow-SWE (Harbor dataset). The nowide::cin , nowide::cout , nowide::cerr , and nowide::clog objects need to be reliable in all usage scenarios, especially on Windows where they transparently convert between UTF‑8…

The task

The `nowide::cin`, `nowide::cout`, `nowide::cerr`, and `nowide::clog` objects need to be reliable in all usage scenarios, especially on Windows where they transparently convert between UTF‑8 and the console’s UTF‑16.

Part of Lego-X/LegoFlow-SWE.