fix(frontend): restore DOMContentLoaded wrapper in app.js and render login overlay by default

app/static/index.html

@@ -5,7 +5,7 @@
     <meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no">
     <title>Notes — Персональный тренажер и словарь английского языка</title>
     <meta name="description" content="Защищённый персональный тренажёр и словарь английского языка с интервальными повторениями SRS SM-2, контекстным поиском и озвучкой">
-    <link rel="stylesheet" href="/static/css/style.css?v=2.9">
+    <link rel="stylesheet" href="/static/css/style.css?v=3.0">
     
     <!-- PWA meta and icons -->
     <link rel="manifest" href="/manifest.json">
@@ -18,7 +18,7 @@
 </head>
 <body>
     <!-- Login Overlay / Page -->
-    <div id="login-overlay" class="login-overlay hidden">
+    <div id="login-overlay" class="login-overlay">
         <div class="login-card">
             <div class="login-header">
                 <div class="login-logo">📖</div>
@@ -928,7 +928,7 @@
     <!-- Audio Element for native streaming -->
     <audio id="global-audio-player" preload="none"></audio>
 
-    <script src="/static/js/app.js?v=2.9"></script>
+    <script src="/static/js/app.js?v=3.0"></script>
 </body>
 </html>
 

app/static/js/app.js

@@ -1,27 +1,28 @@
 // Notes Application Frontend Logic - Complete SRS, Heatmap, Quiz, and Analytics
-    // Persistent session: auto-inject Authorization header if token exists in localStorage
-    const originalFetch = window.fetch;
-    window.fetch = function(url, options = {}) {
-        const token = localStorage.getItem('notes_token');
-        if (token && typeof url === 'string' && url.startsWith('/api/')) {
-            options.headers = options.headers || {};
-            if (options.headers instanceof Headers) {
-                if (!options.headers.has('Authorization')) {
-                    options.headers.set('Authorization', `Bearer ${token}`);
-                }
-            } else if (Array.isArray(options.headers)) {
-                if (!options.headers.some(([k]) => k.toLowerCase() === 'authorization')) {
-                    options.headers.push(['Authorization', `Bearer ${token}`]);
-                }
-            } else {
-                if (!options.headers['Authorization']) {
-                    options.headers['Authorization'] = `Bearer ${token}`;
-                }
+// Persistent session: auto-inject Authorization header if token exists in localStorage
+const originalFetch = window.fetch;
+window.fetch = function(url, options = {}) {
+    const token = localStorage.getItem('notes_token');
+    if (token && typeof url === 'string' && url.startsWith('/api/')) {
+        options.headers = options.headers || {};
+        if (options.headers instanceof Headers) {
+            if (!options.headers.has('Authorization')) {
+                options.headers.set('Authorization', `Bearer ${token}`);
+            }
+        } else if (Array.isArray(options.headers)) {
+            if (!options.headers.some(([k]) => k.toLowerCase() === 'authorization')) {
+                options.headers.push(['Authorization', `Bearer ${token}`]);
+            }
+        } else {
+            if (!options.headers['Authorization']) {
+                options.headers['Authorization'] = `Bearer ${token}`;
             }
         }
-        return originalFetch.call(this, url, options);
-    };
+    }
+    return originalFetch.call(this, url, options);
+};
 
+document.addEventListener('DOMContentLoaded', () => {
     // Register PWA Service Worker
     if ('serviceWorker' in navigator) {
         navigator.serviceWorker.register('/sw.js', { scope: '/' })