[native][web] Expose Secondary device registration RPC to JS

Summary:
Exposed this RPC via Identity context

Depends on D11290

Test Plan: This is tested later in further diffs. Now just ensured it's callable on both native and web

Reviewers: kamil, michal

Reviewed By: kamil

Subscribers: ashoat, tomek

Differential Revision: https://phab.comm.dev/D11291