Build exchange workspace and shared transaction services (#28)

frontend/app/test/kyc_test.dart

@@ -178,7 +178,7 @@ void main() {
     await t.pumpAndSettle();
     await tap(t, find.text('Discard & leave'));
     expect(find.byKey(const ValueKey('kyc-start')), findsNothing);
-    expect(find.text('Explore verification & limits'), findsOneWidget);
+    expect(find.text('Explore your accounts'), findsOneWidget);
   });
   testWidgets('overview controls have accessible labels and touch targets', (
     t,