update LanguageChip icon, enable default shuffling in ExerciseConfig, and refine onClose navigation in VocabularyExerciseHostScreen

app/src/main/java/eu/gaudian/translator/view/exercises/StartExerciseScreen.kt

@@ -406,7 +406,7 @@ fun LanguagePairSection(
                 availablePairs.forEach { pair ->
                     val isSelected = selectedPairs.contains(pair)
                     LanguageChip(
-                        text = "${pair.first.name} → ${pair.second.name}",
+                        text = "${pair.first.name} ⇄ ${pair.second.name}",
                         isSelected = isSelected,
                         modifier = Modifier.widthIn(min = 160.dp),
                         onClick = {

app/src/main/java/eu/gaudian/translator/view/vocabulary/VocabularyExerciseHostScreen.kt

@@ -30,6 +30,7 @@ import eu.gaudian.translator.R
 import eu.gaudian.translator.utils.Log
 import eu.gaudian.translator.utils.findActivity
 import eu.gaudian.translator.view.composable.AppAlertDialog
+import eu.gaudian.translator.view.composable.Screen
 import eu.gaudian.translator.viewmodel.ScreenState
 import eu.gaudian.translator.viewmodel.VocabularyExerciseViewModel
 import eu.gaudian.translator.viewmodel.VocabularyViewModel
@@ -148,7 +149,12 @@ fun VocabularyExerciseHostScreen(
                 onRetryWrong = { _ ->
                     exerciseViewModel.retryWrongAnswers(originalItems)
                 },
-                onClose = onClose
+                onClose = {
+                    navController.navigate(Screen.Home.route) {
+                        popUpTo(Screen.Home.route) { inclusive = true }
+                        launchSingleTop = true
+                    }
+                }
             )
         }
     }

app/src/main/java/eu/gaudian/translator/viewmodel/VocabularyExerciseViewModel.kt

@@ -31,8 +31,8 @@ enum class ScreenState {
 }
 
 data class ExerciseConfig(
-    val shuffleCards: Boolean = false,
-    val shuffleLanguages: Boolean = false,
+    val shuffleCards: Boolean = true,
+    val shuffleLanguages: Boolean = true,
     val trainingMode: Boolean = false,
     val dueTodayOnly: Boolean = false,
     val selectedExerciseTypes: Set<VocabularyExerciseType> = setOf(VocabularyExerciseType.GUESSING),