NEW YORK – The Fireboat John McKean might have figured out this retirement thing after all. Purchased at auction in 2016 — for $57,400, by Westchester restaurateurs Michael Kaphan and Edward Taylor — the McKean, which ferried people to safety and pumped water to the smoldering World Trade Center on 9/11, has had a peripatetic five years. It has been acting more like a Manhattan socialite than a hard-working former member of the FDNY. It flirted with the restaurant business, had run-ins with NIMBY suburban neighbors who complained it blocked their river views, has had some work done and rode out the pandemic out of town.