Donald Trump has taken a commanding lead over Joe Biden — in the world of political meme coins, at least.Crypto tokens linked to former President Trump have leapt in volume and value in recent weeks as the November US presidential election heaves into view and the arch-rivals prepare for their first public debate.The universe of the so-called “PolitiFi” tokens is tiny, with a combined market value of about $1 billion. A majority of those are linked to Trump, who has presented himself as a champion for cryptocurrency although he hasn’t offered specifics on his proposed crypto…