🔔 Webchat Audio Notifications

How to Test:

1. Test sounds: Click "Test Sound" to hear the current intensity level
2. Try different levels: Use the "Sound Intensity" dropdown (Level 1 = whisper, Level 5 = impossible to miss)
3. Find your preference: Test each level to find what works best for you
4. Switch tabs: Open another tab/window
5. Trigger notification: Click "Trigger Notification" button
6. Expected: You should hear a sound (since this tab is hidden)