Yattee v2 rewrite

Yattee/Views/Player/QualitySelector/CardBackgroundModifier.swift

@@ -0,0 +1,31 @@
+//
+//  CardBackgroundModifier.swift
+//  Yattee
+//
+//  Reusable card background modifier for grouped list items.
+//
+
+import SwiftUI
+
+/// Applies platform-appropriate card background with rounded corners.
+///
+/// Uses `ListBackgroundStyle.card` for consistent appearance across platforms.
+struct CardBackgroundModifier: ViewModifier {
+    var cornerRadius: CGFloat = 10
+
+    func body(content: Content) -> some View {
+        content
+            .background(ListBackgroundStyle.card.color)
+            .clipShape(RoundedRectangle(cornerRadius: cornerRadius))
+    }
+}
+
+extension View {
+    /// Applies card background styling used in grouped lists.
+    ///
+    /// - Parameter cornerRadius: The corner radius for the rounded rectangle. Defaults to 10.
+    /// - Returns: A view with card background applied.
+    func cardBackground(cornerRadius: CGFloat = 10) -> some View {
+        modifier(CardBackgroundModifier(cornerRadius: cornerRadius))
+    }
+}