Facing pressure to reduce skyrocketing Chicago violence, Mayor Lori Lightfoot on Friday said her administration will focus this summer on 15 police beats that she said account for a major chunk of the city’s street crime. Police will work in these areas but the city also will team up with community groups, libraries, and other providers to mentor young people as part of Lightfoot’s summer strategy, mirroring her administration’s previous approach to Chicago violence. The beats are largely concentrated on the South and West Sides, ranging from Austin, North Lawndale and West Humboldt Park to South Chicago, Roseland and Auburn Gresham.