fix: update focused game when proxy model count changes

Covers async model load: if count goes 0→N after QML init and currentIndex stays 0, onCurrentIndexChanged never fires. onCountChanged ensures backdrop updates on first population.

src/qml/LibraryView.qml

@@ -96,6 +96,16 @@ FocusScope {
             })
         }
 
+        Connections {
+            target: proxyModel
+            function onCountChanged() {
+                if (proxyModel.count > 0) {
+                    let g = proxyModel.get(grid.currentIndex)
+                    if (g) libraryRoot.gameFocused(g)
+                }
+            }
+        }
+
         delegate: GameCard {
             game: model.gameObject
             gridActive: grid.flickable ? grid.flickable.activeFocus : grid.activeFocus