Fix GraphViz, pin version

index.html

@@ -112,7 +112,7 @@ <h1>Visualize a recursive function</h1>
 
     </div>
     <!-- GraphViz WASM -->
-    <script src="https://cdn.jsdelivr.net/npm/@hpcc-js/wasm/dist/graphviz.umd.js"></script>
+    <script src="https://cdn.jsdelivr.net/npm/@hpcc-js/wasm@2.18.0/dist/graphviz.umd.js"></script>
     <!-- Python WASM -->
     <script src="https://cdn.jsdelivr.net/pyodide/v0.19.0/full/pyodide.js"></script>
     <!-- Form functionality-->
@@ -140,7 +140,7 @@ <h1>Visualize a recursive function</h1>
     <script type="module">
     import {RecursiveTreeViz} from './javascript/recursive_tree_viz.js';
 
-    var hpccWasm = window["@hpcc-js/wasm"];
+    var GraphViz = window["Graphviz"];
     var pyodide;
 
     function computeVisualization() {
@@ -149,7 +149,7 @@ <h1>Visualize a recursive function</h1>
         const functionCall = document.getElementById('function-call-input').value;
         const dotGraph = pyodide.runPython(`visualize('''${functionDef}''', '''${functionCall}''')`);
         document.getElementById("visualize-status").innerHTML = "Rendering call graph...";
-        hpccWasm.Graphviz.load().then(graphviz => {
+        GraphViz.load().then(graphviz => {
               const div = document.getElementById("placeholder");
               div.innerHTML = graphviz.layout(dotGraph, "svg", "dot");
               new RecursiveTreeViz(div.querySelector('svg')).draw()