Apply proposed contact-to-company links

Set the company on contacts that have none, from their email domain.

Applies the proposal GET /directory/contact-company-links returns, or the part of it named by contact_ids. Read that first: a company carrying a consumer domain such as gmail.com claims every personal address in the organization, and this endpoint cannot tell that apart from a real firm.

The proposal is recomputed here rather than carried over from the GET, so contact_ids chooses contacts, not companies: if the company that won a contested domain is archived in between, the runner-up wins this call. The applied list names the company each contact actually got, so compare it against what you reviewed.

Keep the applied list the response returns. It names every contact this call gave a company to, and nothing else records which contacts had none beforehand — so it is what a bad run has to be reversed from.

A contact that already has a company is never touched, whether it had one all along or gained one between the read and this call. Safe to repeat — a second call with nothing left to do links nothing.