Function find_path_bounded 

pub fn find_path_bounded<H>(
    graph: &Graph,
    start: usize,
    goal: usize,
    heuristic: H,
    max_cost: f64,
) -> Option<(f64, Vec<usize>)>
where
    H: Fn(usize) -> f64,

A* algorithm with early termination and path weight limit