fix(playground): ensure local playground is initialized

cli/src/playground.html

@@ -71,6 +71,11 @@
   <script>LANGUAGE_BASE_URL = "";</script>
   <script src=tree-sitter.js></script>
   <script src=playground.js></script>
+  <script>
+    setTimeout(() => {
+      window.initializePlayground()
+    }, 1)
+  </script>
 
   <style>
     body {