replaced account data singleton with a session model

lib/api/marianumconnect/queries/auth_verify/auth_verify.dart

@@ -29,17 +29,12 @@ class AuthVerify extends MarianumConnectQuery {
     required String username,
     required String password,
   }) async {
-    final token = await _tokenStorage.readToken();
-    if (token == null || token.isEmpty) {
-      throw AuthException.unauthorized(
-        technicalDetails: 'AuthVerify: no bearer token in storage',
-      );
-    }
+    final options = await _tokenStorage.requireBearerOptions('AuthVerify');
     return guard(() async {
       await dio.post<void>(
         endpoint('auth/verify'),
         data: {'username': username, 'password': password},
-        options: Options(headers: {'Authorization': 'Bearer $token'}),
+        options: options,
       );
     });
   }