[Bug libstdc++/94674] std::ranges::basic_istream_view::iterator is missing std::iterator_traits entries

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94674

--- Comment #4 from Jonathan Wakely <redi at gcc dot gnu.org> ---
That iterator doesn't have a pointer type, because in the new Ranges world that
type is not useful. It is no longer required for iterators to have operator->
so what does the 'pointer' type even mean?