Switch notification sound to hohoho.mp3 and add download script

Replaced all references to notification.mp3 with hohoho.mp3 in notification-related components and context. Added hohoho.mp3 to the public directory. Introduced a script (download-notification-sound.js) for downloading notification sounds from YouTube using @distube/ytdl-core, which was added as a devDependency. Also added yt-dlp.exe for alternative audio downloading.

scripts/download-notification-sound.js

@@ -0,0 +1,74 @@
+/**
+ * Script to download notification sound from YouTube
+ * Uses @distube/ytdl-core to download audio
+ */
+
+const ytdl = require('@distube/ytdl-core');
+const fs = require('fs');
+const path = require('path');
+
+const YOUTUBE_URL = 'https://www.youtube.com/watch?v=utmKQWAuYH4';
+const OUTPUT_PATH = path.join(__dirname, '..', 'public', 'notification.mp3');
+
+console.log('Downloading notification sound from YouTube...');
+console.log(`URL: ${YOUTUBE_URL}`);
+console.log(`Output: ${OUTPUT_PATH}`);
+
+async function downloadAudio() {
+  try {
+    // Validate URL
+    if (!ytdl.validateURL(YOUTUBE_URL)) {
+      throw new Error('Invalid YouTube URL');
+    }
+
+    // Get video info
+    console.log('\nFetching video information...');
+    const info = await ytdl.getInfo(YOUTUBE_URL);
+    console.log(`Title: ${info.videoDetails.title}`);
+
+    // Get audio format
+    const audioFormats = ytdl.filterFormats(info.formats, 'audioonly');
+    if (audioFormats.length === 0) {
+      throw new Error('No audio formats available');
+    }
+
+    // Select best quality audio
+    const format = audioFormats[0];
+    console.log(`\nDownloading audio format: ${format.audioCodec || 'unknown'}`);
+
+    // Create write stream
+    const outputStream = fs.createWriteStream(OUTPUT_PATH);
+    
+    // Download audio
+    const audioStream = ytdl.downloadFromInfo(info, { format });
+    
+    audioStream.pipe(outputStream);
+    
+    audioStream.on('progress', (chunkLength, downloaded, total) => {
+      const percent = (downloaded / total * 100).toFixed(2);
+      process.stdout.write(`\rDownloaded: ${percent}%`);
+    });
+
+    await new Promise((resolve, reject) => {
+      outputStream.on('finish', () => {
+        console.log('\n\n✅ Successfully downloaded notification sound!');
+        resolve();
+      });
+      outputStream.on('error', reject);
+      audioStream.on('error', reject);
+    });
+
+  } catch (error) {
+    console.error('\n❌ Error downloading audio:', error.message);
+    console.error('\nAlternative options:');
+    console.log('1. Install yt-dlp: pip install yt-dlp');
+    console.log('2. Download executable: https://github.com/yt-dlp/yt-dlp/releases');
+    console.log('3. Use online converter');
+    console.log('\nThen run:');
+    console.log(`yt-dlp -x --audio-format mp3 --audio-quality 0 -o "public/notification.mp3" "${YOUTUBE_URL}"`);
+    process.exit(1);
+  }
+}
+
+downloadAudio();
+