Complete JavaScript initialization fix

- Add missing backend selector initialization
- Add podcast list initialization calls
- Ensure complete app startup sequence matches original init() function
- All event listeners and UI components now properly initialize

frontend/app.js

@@ -847,7 +847,74 @@ async function downloadEpisode(audioUrl, title, triggerButton = null) {
     console.error(err);
     setStatus(err.message, 'error');
   } finally {
-    triggerButton.classList.remove('loading');
-    triggerButton.textContent = 'Download';
+    if (triggerButton) {
+      triggerButton.classList.remove('loading');
+      triggerButton.textContent = originalLabel || 'Download';
+    }
   }
 }
+
+// Initialize the application
+document.addEventListener('DOMContentLoaded', async () => {
+  // Initialize tabs
+  initTabs();
+
+  // Initialize sidebar interactions
+  initSidebarInteractions();
+
+  // Initialize audio interactions
+  initAudioInteractions();
+
+  // Load configuration
+  await fetchConfig();
+
+  // Initialize backend selector
+  elements.backendSelect.innerHTML = `
+    <option value="moonshine">Moonshine</option>
+    <option value="sensevoice" selected>SenseVoice</option>
+  `;
+  state.backend = elements.backendSelect.value;
+
+  // Initialize podcast lists
+  setListEmpty(elements.podcastResults, 'Search to discover podcasts.');
+  setListEmpty(elements.episodeResults, 'Select a podcast to view episodes.');
+
+  // Set up podcast interactions
+  elements.podcastResults.addEventListener('click', (event) => {
+    const button = event.target.closest('button[data-feed]');
+    if (button) {
+      const feedUrl = button.dataset.feed;
+      const sourceItem = button.closest('.list-item');
+      loadEpisodes(feedUrl, sourceItem);
+    }
+  });
+
+  elements.episodeResults.addEventListener('click', (event) => {
+    const button = event.target.closest('button[data-url]');
+    if (button) {
+      const audioUrl = button.dataset.url;
+      const title = button.dataset.title;
+      downloadEpisode(audioUrl, title, button);
+    }
+  });
+
+  elements.podcastQuery.addEventListener('keydown', (event) => {
+    if (event.key === 'Enter') {
+      event.preventDefault();
+      handlePodcastSearch();
+    }
+  });
+
+  // Set up other event listeners
+  elements.transcribeBtn.addEventListener('click', handleTranscription);
+  elements.summaryBtn.addEventListener('click', handleSummaryGeneration);
+  elements.detectSpeakerNamesBtn.addEventListener('click', handleSpeakerNameDetection);
+  elements.exportTranscriptBtn.addEventListener('click', handleExportTranscript);
+  elements.exportSummaryBtn.addEventListener('click', handleExportSummary);
+  elements.fileInput.addEventListener('change', handleFileUpload);
+  elements.youtubeFetch.addEventListener('click', handleYoutubeFetch);
+  elements.podcastSearch.addEventListener('click', handlePodcastSearch);
+
+  // Set initial status
+  setStatus('Ready', 'info');
+});