Just to clarify. The gi:// resources are GObject Introspection modules which are used for multilanguage bindings to native libraries. On my system, GI modules are found in /usr/share/gir-1.0/ . They’re just imported by name and sometimes version using gi:// (there are examples in the link in my first comment).
As I don’t have Gnome installed I can’t be sure of the path to gnome shell modules imported using resource://, but it’s probably the path I wrote, but without js/.