Mr. Trump sent Mr. Musk, the head of the Department of Government Effectiveness, off at a White House news conference on Friday. At the event, Mr. Trump handed Mr. Musk a wooden box containing a gold key to the White House as a reward for his role as a special government employee. After receiving the gift, Mr. Musk praised Mr. Trump's redesign of the Oval Office. "I love the gold on the ceiling," Mr. Musk said. "That's 24k gold," Mr. Trump quipped. "Thanks to the president, the Oval Office final...