The US won’t repeat the mistakes of the Iraq War by failing to secure valuable resources from Ukraine in exchange for help ending Russia’s nearly three-year-old invasion, President Trump’s special envoy to the conflict exclusively told The Post. “When you look at the mineral deposits in that country, we’re not talking millions of dollars. We’re talking — virtually every region, we’re talking about billions, and then some regions are [worth] trillions,” retired Gen. Keith Kellogg said this week. “You can come up with a deal, and that’s what [Trump] has the Treasury looking at: ‘OK, how do you make a...