Fixed

The iterative search code in planner.cc/main looks like this:

        if (engine->found_solution()) {
            save_plan(engine->get_plan());
            wastar_bound = engine->get_plan().size();
        } else {
            iterative_search = false;
        }

The line
            wastar_bound = engine->get_plan().size();
is fine for unit-cost problems, but in general this should be the total cost of
the plan, not its length.