Real estate firm Reuben Brothers is betting on the future of urban air travel, unveiling plans to bring a luxury “vertiport” to Century City through a partnership with Joby Aviation. The proposed hub would sit atop the South Tower of the affluent Park Elm Residences at Century Plaza, repurposing an existing helipad to support Joby’s all-electric vertical takeoff and landing aircraft, or eVTOLs — a technology Joby says could dramatically cut travel times across Los Angeles.