Integrate email notifications into signup and login (#38)

frontend/app/lib/auth/form.dart

@@ -104,6 +104,11 @@ class _AuthFormState extends State<AuthForm> {
         locale: locale,
       );
       if (!mounted || _signUp) return;
+      if (login.state.error == AuthError.accountNotVerified) {
+        _password.clear();
+        context.goNamed(AppRoutes.verificationSent, extra: _email.text.trim());
+        return;
+      }
       final challenge = login.state.result?.challenge;
       if (challenge != null) {
         _password.clear();
@@ -329,10 +334,11 @@ class _AuthFormState extends State<AuthForm> {
           AuthFeedback(state: state, signUp: _signUp),
         ],
         const SizedBox(height: 20),
-        TextButton(
-          onPressed: () => context.go('/accounts'),
-          child: Text(l.wEnter),
-        ),
+        if (context.read<TwoFactorService>().isSimulated)
+          TextButton(
+            onPressed: () => context.go('/accounts'),
+            child: Text(l.wEnter),
+          ),
         Wrap(
           alignment: WrapAlignment.center,
           crossAxisAlignment: WrapCrossAlignment.center,