Focus the delayed tvOS Cancel when it appears

By the time the button shows, focus has already been lost, and the
focus engine is not guaranteed to pick up an element inserted later.

Yattee/Views/Components/LoadStateView.swift

@@ -61,16 +61,22 @@ struct TVStalledLoadCancelButton: View {
     let action: () -> Void
 
     @State private var isShown = false
+    @FocusState private var isFocused: Bool
 
     var body: some View {
         Group {
             if isShown {
                 Button(String(localized: "common.cancel"), action: action)
+                    .focused($isFocused)
             }
         }
         .task {
             guard (try? await Task.sleep(for: delay)) != nil else { return }
             isShown = true
+            // Focus was already lost by the time the button appears, and the
+            // focus engine is not guaranteed to pick up a late arrival.
+            guard (try? await Task.sleep(for: .milliseconds(100))) != nil else { return }
+            isFocused = true
         }
     }
 }