fix：商城登录互通问题

test/features/mall/mall_auth_api_test.dart

@@ -0,0 +1,92 @@
+import 'dart:convert';
+import 'dart:typed_data';
+
+import 'package:dio/dio.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:jinzhi_flutter_app/features/mall/data/mall_auth_api.dart';
+
+void main() {
+  test('sends an empty protobuf body when issuing a mall auth token', () async {
+    Object? requestData;
+    String? contentType;
+    final dio = Dio()
+      ..interceptors.add(
+        InterceptorsWrapper(
+          onRequest: (options, handler) {
+            requestData = options.data;
+            contentType = options.contentType;
+            handler.resolve(
+              Response<List<int>>(
+                requestOptions: options,
+                statusCode: 200,
+                data: _validResponse(),
+              ),
+            );
+          },
+        ),
+      );
+
+    final token = await MallAuthApi(dio).issueAppMallAuthToken();
+
+    expect(requestData, isA<Uint8List>());
+    expect(requestData, isEmpty);
+    expect(contentType, 'application/x-protobuf');
+    expect(token.authToken, 'mall-token');
+    expect(token.expiresIn, 300);
+    expect(token.sourceApp, 'jinzhi');
+    expect(token.scene, 'web_mall');
+  });
+
+  test('rejects an incomplete mall auth token response', () async {
+    final dio = Dio()
+      ..interceptors.add(
+        InterceptorsWrapper(
+          onRequest: (options, handler) {
+            handler.resolve(
+              Response<List<int>>(
+                requestOptions: options,
+                statusCode: 200,
+                data: _stringField(1, 'mall-token'),
+              ),
+            );
+          },
+        ),
+      );
+
+    await expectLater(
+      MallAuthApi(dio).issueAppMallAuthToken(),
+      throwsFormatException,
+    );
+  });
+}
+
+List<int> _validResponse() => <int>[
+  ..._stringField(1, 'mall-token'),
+  ..._integerField(2, 300),
+  ..._stringField(3, 'jinzhi'),
+  ..._stringField(4, 'web_mall'),
+];
+
+List<int> _stringField(int field, String value) {
+  final bytes = utf8.encode(value);
+  return <int>[
+    ..._varint((field << 3) | 2),
+    ..._varint(bytes.length),
+    ...bytes,
+  ];
+}
+
+List<int> _integerField(int field, int value) => <int>[
+  ..._varint(field << 3),
+  ..._varint(value),
+];
+
+List<int> _varint(int value) {
+  final bytes = <int>[];
+  while (value > 0x7f) {
+    bytes.add((value & 0x7f) | 0x80);
+    value >>= 7;
+  }
+  bytes.add(value);
+  return bytes;
+}