WASHINGTON — House investigators are laying out the origins of the violence at the U.S. Capitol on Jan. 6, 2021, using video testimony and live witnesses to describe former President Donald Trump’s “call to action” in a December tweet and how White House advisers urged the president to drop his false claims of election fraud.At its seventh public hearing, the Jan. 6 panel is not only detailing the plans of extremist groups like the Proud Boys and Oath Keepers ahead of the attack, but is keeping its …