LWG4492. std::generate and std::ranges::generate wording is unclear for parallel algorithms

[jwakely]

https://cplusplus.github.io/LWG/issue4492

LWG approved this issue today, striking the new parallel overloads of ranges::generate and ranges::generate_n. As explained in the issue, there are open questions about the semantics of the existing parallel std::generate which need to be resolved before we add new parallel versions to namespace ranges. The conservative approach seems to be to not add new functions in C++26 until we've clarified the semantics of the existing algorithms (which will be done via a new library issue, to be opened soon). Once we know what they should do, we can decide whether to add them back again for C++29.

We would like LEWG to confirm whether removing these new functions (added to C++26 by P3179R9) is the right approach for C++26.