challenger: Introduce supernode provider

[Inphi]

Integrate a supernode provider to eventually replace the supervisor provider. Since the supernode API isn't fully implemented yet, the challenger should continue using the supervisor provider to maintain e2e testing coverage. Ideally, we can hide both API variants behind a unified interface to make the eventual migration to supernode seamless. I suggest refactoring the super.RootProvider interface and the SuperTraceProvider to accommodate both APIs.