Krystian's Q4 2023 Update

https://cppalliance.org/krystian/2024/01/12/KrystianQ4Update.html

During Q4, enhancements were made to MrDocs to render overload sets, support friend declarations, deduction guides, enumerators, and to replace prior TypeInfo variants with a unified SymbolName type. clang work progressed on C++ conformance fixes and a patch to improve dependent name lookup diagnostics.