Sort flashcard list by favorite first

add mock favorite data to preview

WordAX/Model/DataController.swift

@@ -33,6 +33,7 @@ class DataController: ObservableObject {
             flashcard.lastSeenOn = [nil, Date(), Date().addingTimeInterval([-86400, -24000, -100000].randomElement()!)].randomElement()!
             flashcard.shownCount = [0, 1, 2, 3, 4, 5].randomElement()!
             flashcard.dateAdded = [Date(), Date().addingTimeInterval(-86400), Date().addingTimeInterval(-172800)].randomElement()!
+            flashcard.favorite = [true, false].randomElement()!
         }
         do {
             try viewContext.save()

WordAX/Views/FlashCardListView.swift

@@ -10,7 +10,7 @@ import SwiftUI
 struct FlashCardListView: View {
     @State var showDescription = true
     @State var addFlashcard = false
-    @FetchRequest(sortDescriptors: [NSSortDescriptor(key: "dateAdded", ascending: false)]) var flashcards: FetchedResults<Flashcard>
+    @FetchRequest(sortDescriptors: [NSSortDescriptor(key: "favorite", ascending: false), NSSortDescriptor(key: "dateAdded", ascending: false)]) var flashcards: FetchedResults<Flashcard>
     @Environment(\.managedObjectContext) var moc
     var body: some View {
         GeometryReader { geometry in