WASHINGTON — President Trump plans to unveil a new White House office on Monday with sweeping authority to overhaul the federal bureaucracy and fulfill key campaign promises – such as reforming care for veterans and fighting opioid addiction – by harvesting ideas from the business world and, potentially, privatizing some government functions. The White House Office of American Innovation, to be led by Jared Kushner, the president’s son-in-law and senior adviser, will operate as its own nimble power center within the West Wing and will report directly to Trump.