fix: add WASM init error handling to index page

docs_v1.0/doc_wasm/index.html

@@ -85,7 +85,10 @@ async function checkAuth() {
 }
 
 async function initApp() {
+  const el = document.getElementById('content');
+  try {
     await init();
+    el.innerHTML = '<p>WASM initialized. Loading modules...</p>';
     
     // Parse module list
     modules = JSON.parse(module_list());
@@ -113,6 +116,9 @@ async function initApp() {
     } else {
       loadDoc('01_auth');
     }
+  } catch(e) {
+    el.innerHTML = `<p style="color:red">WASM init error: ${e.message}</p><pre>${e.stack}</pre>`;
+  }
 }
 
 // Handle browser back/forward
@@ -121,6 +127,7 @@ window.onpopstate = () => {
   if (hash) loadDoc(hash);
 };
 
+document.getElementById('content').innerHTML = '<p>Starting WASM...</p>';
 initApp();
 </script>
 </body>