Fixed arrows broken on resize or img load

projects/script.js

@@ -112,5 +112,7 @@ document.querySelectorAll('.node').forEach(node => {
 });
 
 // ─── Initial draw ─────────────────────────────────────────────
-// Wait two frames so the browser has laid out the divs
+window.addEventListener('load', redraw);
-requestAnimationFrame(() => requestAnimationFrame(redraw));
+
+// also redraws if anything inside the scene changes size
+new ResizeObserver(redraw).observe(scene);