Keep back stack of navigation controller clean.

app/src/main/java/me/zobrist/tichucounter/domain/NavExtensions.kt

@@ -5,7 +5,19 @@ import androidx.navigation.*
 import androidx.navigation.compose.composable
 
 fun NavController.navigate(route: Route) {
-    this.navigate(route.name)
+    this.navigate(route.name){
+        // Pop up to the start destination of the graph to
+        // avoid building up a large stack of destinations
+        // on the back stack as users select items
+        popUpTo(Route.COUNTER.name) {
+            saveState = true
+        }
+        // Avoid multiple copies of the same destination when
+        // reselecting the same item
+        launchSingleTop = true
+        // Restore state when reselecting a previously selected item
+        restoreState = true
+    }
 }
 
 fun NavGraphBuilder.composable(