add comment about minimax

src/logic/future_moves.rs

@@ -291,6 +291,7 @@ impl FutureMoves {
                 self.arena[x]
                     .children
                     .iter()
+                    // this would be considered `minimax`
                     .max_by_key(|&&idx| self.arena[idx].value)
             })
             .inspect(|&&x| {