refac day 14 to use new Vec2.bounds function

src/day14.ml

@@ -44,18 +44,8 @@ let draw_rocks grid points =
 
 let parse_grid lines start =
   let points = List.map parse_line lines in
-  let lx, hx, ly, hy =
-    points
-    |> List.flatten
-    |> List.append [ start ]
-    |> List.fold_left
-         (fun (lx, hx, ly, hy) Vec2.{ x; y } ->
-           let lx = min lx x in
-           let hx = max hx x in
-           let ly = min ly y in
-           let hy = max hy y in
-           lx, hx, ly, hy)
-         (Int.max_int, 0, Int.max_int, 0)
+  let Vec2.{ x = lx; y = ly }, Vec2.{ x = hx; y = hy } =
+    points |> List.flatten |> List.append [ start ] |> Vec2.bounds 0
   in
   let pad_floor = 1 in
   let pad_x = 2 in