This patch adds 2 new attributes to `DemangledNameInfo`: `TemplateRange` and `NameQualifiersRange`. It also introduces the `function.name-qualifiers` entity formatter which allows tracking qualifiers between the name of a function and its arguments/template. This will be used downstream in Swift but may have applications in C++: https://github.com/swiftlang/llvm-project/pull/11068.