This week we finally got a peek at the master plan for redeveloping Westfield Montgomery mall into a living, working, shopping and dining community a la Pike & Rose. Most of the mall will remain intact — with the exception of Sears, which finally will close its doors next March — but plans calls for extensive additions including office space, apartments, a hotel, pedestrian walkways, and outdoor promenades lined with upscale stores and restaurants. Also on the way: a large fitness center with a dedicated parking lot. (No names have been revealed yet, but we’re hearing it’s Equinox.) The entire expansion plan will take about four years, beginning in spring 2019 after Sears is torn down.