Fix JS loadFileTree error and add favicon

backend/static/app.js

@@ -13,7 +13,6 @@ class TranscriptionApp {
     init() {
         this.connectWebSocket();
         this.setupUpload();
-        this.loadFileTree();
     }
 
     // ===== WebSocket =====

backend/static/index.html

@@ -4,6 +4,7 @@
     <meta charset="UTF-8">
     <meta name="viewport" content="width=device-width, initial-scale=1.0">
     <title>Транскрибация совещаний</title>
+    <link rel="icon" href="data:image/svg+xml,<svg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 100 100'><text y='.9em' font-size='90'>🎙️</text></svg>">
     <link rel="stylesheet" href="/static/styles.css">
     <!-- Markdown renderer -->
     <script src="https://cdn.jsdelivr.net/npm/marked/marked.min.js"></script>