“I really don’t know what he said at the end of that sentence. I don’t think he knows what he said, either.” With those words, Donald Trump effectively ended the first presidential debate — and the entirety of the debate regarding President Joe Biden’s mental fitness, really — with a TKO, literally before the 90-minute contest hit the half-hour mark. Trump: “I really don’t know what he said at the end of that sentence; I don’t think he knows what he said either.” pic.twitter.com/afW9TkIuUV — The Post Millennial (@TPostMillennial) June 28, 2024 The only question that remained, for those of us…