Audio UX (UI) + bottom bar rework: two-line footer (dropped/duration under bitrate/fps), centered sound meter (blank→green→yellow→red, zone markers at 60%/80%) + MIC chip (MicVolume slider, ToggleMicMuteCommand) — the mic is the creator's only audio control, desktop/game audio is automatic (KISS rule); scenes list is content-height (no dead space before SOURCES); top bar shows the connected YT account avatar/name via SyncConnectedAccount; docs updated (65 tests passing)

ViewModels/MainViewModel.cs

@@ -27,6 +27,11 @@ public class MainViewModel : ViewModelBase
     private SceneElement? _selectedElement;
     private ImageSource? _activeBackgroundImage;
     private bool _isConnected;
+    private string _accountAvatarUrl = string.Empty;
+    private string _accountDisplayName = string.Empty;
+    private double _audioLevel;
+    private double _micVolume = 1.0;
+    private bool _micMuted;
     private StreamStatus _streamStatus = StreamStatus.Offline;
     private StreamHealth _currentHealth = new();
     private string _streamTitle = string.Empty;
@@ -187,6 +192,65 @@ public class MainViewModel : ViewModelBase
         }
     }
 
+    /// <summary>The connected YouTube account's avatar + name — shown in the top
+    /// bar so the creator always sees WHICH account is about to go live.</summary>
+    public string AccountAvatarUrl
+    {
+        get => _accountAvatarUrl;
+        private set => SetProperty(ref _accountAvatarUrl, value);
+    }
+
+    public string AccountDisplayName
+    {
+        get => _accountDisplayName;
+        private set => SetProperty(ref _accountDisplayName, value);
+    }
+
+    // ─── Audio (KISS: desktop/game audio is automatic — zero UI. The creator's
+    // ─── only audio control is the mic: meter + volume + mute.) ───
+
+    /// <summary>Current level 0..1 — fed by the audio mixer once capture lands.
+    /// Drives the sound meter's fill width + zone color.</summary>
+    public double AudioLevel
+    {
+        get => _audioLevel;
+        set
+        {
+            if (SetProperty(ref _audioLevel, Math.Clamp(value, 0, 1)))
+            {
+                OnPropertyChanged(nameof(MeterFillWidth));
+                OnPropertyChanged(nameof(MeterBrush));
+            }
+        }
+    }
+
+    public double MeterFillWidth => AudioLevel * 360;
+
+    public string MeterBrush => AudioLevel switch
+    {
+        < 0.6 => "#22c55e",
+        < 0.8 => "#eab308",
+        _ => "#ef4444",
+    };
+
+    public double MicVolume
+    {
+        get => _micVolume;
+        set => SetProperty(ref _micVolume, Math.Clamp(value, 0, 1));
+    }
+
+    public bool MicMuted
+    {
+        get => _micMuted;
+        set
+        {
+            if (SetProperty(ref _micMuted, value))
+                OnPropertyChanged(nameof(MicMuteText));
+        }
+    }
+
+    public string MicMuteText => MicMuted ? "Unmute" : "Mute";
+
     public bool IsOffline => StreamStatus == StreamStatus.Offline;
     public bool IsLive => StreamStatus == StreamStatus.Streaming;
     public bool LiveIndicatorVisible => IsLive;
@@ -533,6 +597,7 @@ public class MainViewModel : ViewModelBase
     public ICommand ChangeCaptureCommand { get; }
     public ICommand RefreshCaptureCommand { get; }
     public ICommand SetBackdropDisplayCommand { get; }
+    public ICommand ToggleMicMuteCommand { get; }
     public ICommand StartStreamCommand { get; }
     public ICommand EndStreamCommand { get; }
     public ICommand OpenSettingsCommand { get; }
@@ -587,6 +652,7 @@ public class MainViewModel : ViewModelBase
         ChangeCaptureCommand = new RelayCommand(_ => _ = ChangeBackdropCaptureAsync());
         RefreshCaptureCommand = new RelayCommand(_ => RefreshBackdropAutoCapture());
         SetBackdropDisplayCommand = new RelayCommand(display => SetBackdropCapture(display as DisplayInfo));
+        ToggleMicMuteCommand = new RelayCommand(_ => MicMuted = !MicMuted);
         OpenSettingsCommand = new RelayCommand(_ => ShowOverlay(nameof(IsSettingsOpen), "App Settings"));
         OpenBugCommand = new RelayCommand(_ => ShowOverlay(nameof(IsBugOpen), "Report Bug"));
         OpenFeatureCommand = new RelayCommand(_ => ShowOverlay(nameof(IsFeatureOpen), "Feature Request"));
@@ -651,6 +717,7 @@ public class MainViewModel : ViewModelBase
             }
 
             IsConnected = true;
+            SyncConnectedAccount();
         }
         catch (Exception ex)
         {
@@ -658,6 +725,13 @@ public class MainViewModel : ViewModelBase
         }
     }
 
+    private void SyncConnectedAccount()
+    {
+        var channel = _youtubeAuth.CurrentChannel;
+        AccountAvatarUrl = channel?.ProfileImageUrl ?? string.Empty;
+        AccountDisplayName = channel?.DisplayName ?? string.Empty;
+    }
+
     private static string DefaultLayoutPath => Path.Combine(
         Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData),
         "ytLlive",
@@ -1443,6 +1517,7 @@ public class MainViewModel : ViewModelBase
             }
 
             IsConnected = true;
+            SyncConnectedAccount();
             return channel;
         }
         catch (Exception ex)
@@ -1494,6 +1569,7 @@ public class MainViewModel : ViewModelBase
         _youtubeAuth.ClearSession();
         TokenStore.Clear();
         IsConnected = false;
+        SyncConnectedAccount();
         AppLog.Write("Stream ended; session signed out");
     }