My opinion, the external wall framing needs to be designed and inspected by an engineer. In my locality, it is common for the wall framing supplier to design and certify the installation of their product. As the engineer who oversee's the project, I request that the wall framing contractor submits shop drawings 7 days prior to fabrication for review. This is not to critique their design, it is to ensure that nothing is missed between the overlap of my 'structural design' and the wall framing contractors design.
If it is a non-loadbearing situation and none of the stud infill forms part of the bracing system, I would just specify on the drawings that the metal stud walls are by the wall framing subcontractor. If I wanted some movement between the stud walls and the steelwork, I would say that the top track is to allow +/-0.5" vertical movement.