Complete verification links and preserve verified login email (#60)

frontend/packages/sxchnge_auth/lib/src/models/verification.dart

@@ -17,15 +17,22 @@ class VerificationException implements Exception {
 }
 
 class VerificationResult {
-  const VerificationResult({required this.isSimulated});
+  const VerificationResult({required this.isSimulated, this.verifiedEmail});
   final bool isSimulated;
+  final String? verifiedEmail;
 }
 
 class VerificationState {
-  const VerificationState(this.status, {this.isSimulated = false, this.error});
+  const VerificationState(
+    this.status, {
+    this.isSimulated = false,
+    this.error,
+    this.result,
+  });
   final VerificationStatus status;
   final VerificationError? error;
   final bool isSimulated;
+  final VerificationResult? result;
   bool get isLoading =>
       status == VerificationStatus.sending ||
       status == VerificationStatus.checking;