implement staging api

klondike-bench/src/main.rs

@@ -21,7 +21,9 @@ fn play_to_win(rng: &mut Rng) -> Option<KlondikeStats> {
 			return None;
 		}
 
-		game.process_instruction(&mut stats, &CONFIG, instruction);
+		game.stage_instruction(&mut stats, &CONFIG, instruction)
+			.unwrap()
+			.commit();
 	}
 	game.is_win().then_some(stats)
 }