secondMomentStarSelector is very old and fragile code, and "has been basically fully superseded by objectSizeStarSelector" (quoting Jim Bosch). We should just remove it.
Convert makePsfCandidates into its own task
Cleanup and unify star selector call signatures
Move makePsfCandidates into its own task
With no objections, and a relatively trivial removal, I'm going to adopt this.