"My shared gists" should only show gists applicable to the host, not all gists

[Zlatkovsky]

E.g., for a web (or Word) snippet, shouldn't be seeing the Excel ones:

[Zlatkovsky]

Relevant code is under

loadGists$: Observable<Action> = this.actions$

How do we do this efficiently? Should we actually put the host in the filename (e.g., "auth works - mz.web.yaml")?