The Barclays Center arena in downtown Brooklyn is expanding its arts programming in the service of “Brooklyn Art Encounters,” a new multi-year initiative to continue public art presentations on the building’s high-profile plaza but also move into other realms including an artist-in-residence program to be inaugurated by Paul Pfeiffer.   Pfeiffer, whose work has engaged the spectacle around sports, will lead what a press release describes as “a year-long media workshop engaging justice-impacted youth and adults from surrounding communities” in collaboration with artist Shaun Leonardo. With support from the Social Justice Fund, the two artists will provide training in video production, storytelling, and media practices, as well as behind-the-scenes access to Barclays Center operations during live events, including broadcasting, security, and concessions.   Related Articles That begins in May, when a new “Art on the Hour” series of digital artworks will also start broadcasting 60-second artworks on the arena’s looming “Oculus” LED screen. In the fall, Sarah Sze will premiere Wave, a new commissioned work “suspending over 250 animated projected images in a wave like …