WASHINGTON — Sen. Ted Cruz signaled a bruising fight Thursday if the White House pushes ahead with the nominee for a coveted Caribbean diplomatic post who spread unfounded conspiracy theories about him during the 2016 campaign. As an ardent cheerleader for Donald Trump, beauty supply executive Leandro Rizzuto Jr. used Twitter to promote an unsubstantiated allegation that Cruz cheated on his wife, and other claims that Heidi Cruz herself was part of a cabal seeking to unite North America under one government. "I don't know the fellow. He seems to have unusual views," Cruz said Thursday through an aide. "I...