gh-131238: Move _Py_VISIT_STACKREF() to pycore_stackref.h (#131560)

* Move _Py_VISIT_STACKREF() from pycore_gc.h to pycore_stackref.h.
* Remove pycore_interpframe.h include from pycore_genobject.h.
* Remove now useless includes from C files.
* Add pycore_interpframe_structs.h to Makefile.pre.in and
  pythoncore.vcxproj.