The C#/Roslyn-form ID of a member whose C++/CLI form differs can equal
the only key of a same-named sibling overload (char* vs signed char*).
Assemblies containing such overloads cannot come from the C# compiler,
so their xml files use the C++/CLI dialect, where that key documents
the sibling: falling back to the Roslyn form would show the sibling's
documentation for an undocumented member. GetIdStringCandidates now
omits the Roslyn form when a same-named sibling's C++/CLI form owns it,
so a lookup miss stays a miss.
Assisted-by: Claude:claude-fable-5:Claude Code
Siegfried Pammer