Project part display names are bad for cmake projects

The name of a project part is user-facing. For instance, it is shown when the user has to choose between parse contexts when the same file is part of several products.

For cmake, we get display names such as "Core::@e8138540d8b2daa0b357_cg1", which does not allow the user to make an informed decision if the first part is the same.

If it's not possible to have "speaking names" there, we should probably present the origin in such a way that the user can look it up, e.g. project file path + line number.