Right rail, top bar, bottom bar and chat border: Socials slide-out drawer, tab icons and colors, EDIT toggle, stream readouts moved to the top-left cell, webcam border restored, chat border controls, 30fps vertical tier

- Socials: the dialog is a right-rail drawer (same pattern as Stream Info/YPP/TEST); the live-screen button is removed
- Right rail: Stream Info (was Stream Settings) and YPP show the YouTube logo; Socials and TEST get icons; tab colors and label colors per spec
- Top bar: EDIT toggle beside REC (orange when on, blue when off); going live on YouTube turns it off
- Stream readouts (bitrate, FPS, dropped n (x.y%), Live hh:mm:ss, health) and the resolution dropdown moved to the top-left cell; bottom bar emptied at the same height
- Webcam border drawing restored (it was removed with the CRT bezel change)
- YouTube chat layer: border color, thickness, and opacity controls
- Vertical 1080p30 tier added

Not related to the fps gate yet; no gating is enforced.

Helpers/DroppedFramesToBrushConverter.cs

@@ -0,0 +1,23 @@
+using System.Globalization;
+using System.Windows.Data;
+using System.Windows.Media;
+
+namespace ytLive.Helpers;
+
+public class DroppedFramesToBrushConverter : IValueConverter
+{
+    private static readonly SolidColorBrush Attention = new(Color.FromRgb(0xff, 0x8c, 0x3a));
+    private static readonly SolidColorBrush Clean = new(Colors.White);
+
+    static DroppedFramesToBrushConverter()
+    {
+        Attention.Freeze();
+        Clean.Freeze();
+    }
+
+    public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
+        => value is int dropped && dropped > 0 ? Attention : Clean;
+
+    public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
+        => throw new NotSupportedException();
+}