WASHINGTON (Reuters) -Laura Loomer once had to chain herself to a building to get attention. A far-right activist who has jockeyed her way up from online agitator to self-appointed presidential adviser, Loomer has long been one of President Donald Trump’s most fervent supporters. She has recently found herself at odds with the White House, however, clashing with the administration over both policy and personnel choices that she views as counter to the MAGA movement.