fix navbar freezing fix

test/app_shell_test.dart

@@ -0,0 +1,20 @@
+import 'package:flutter_test/flutter_test.dart';
+import 'package:mileograph_flutter/ui/app_shell.dart';
+
+void main() {
+  test('tabIndexForPath maps nested routes', () {
+    expect(tabIndexForPath('/'), 0);
+    expect(tabIndexForPath('/calculator'), 1);
+    expect(tabIndexForPath('/calculator/details'), 1);
+    expect(tabIndexForPath('/legs'), 2);
+    expect(tabIndexForPath('/traction/12/timeline'), 3);
+    expect(tabIndexForPath('/trips'), 4);
+    expect(tabIndexForPath('/add'), 5);
+  });
+
+  test('tabIndexForPath ignores query when parsing uri', () {
+    expect(tabIndexForPath(Uri.parse('/trips?sort=desc').path), 4);
+    expect(tabIndexForPath(Uri.parse('/calculator/details?x=1').path), 1);
+  });
+}
+