feat: 未读消息计数

lib/http/api.dart

@@ -539,4 +539,7 @@ class Api {
   /// 关闭会话
   static const String removeSession =
       '${HttpString.tUrl}/session_svr/v1/session_svr/remove_session';
+
+  /// 消息未读数
+  static const String unread = '${HttpString.tUrl}/x/im/web/msgfeed/unread';
 }

lib/http/msg.dart

@@ -225,4 +225,16 @@ class MsgHttp {
       return {'status': false, 'date': [], 'msg': res.data['message']};
     }
   }
+
+  static Future unread() async {
+    var res = await Request().get(Api.unread);
+    if (res.data['code'] == 0) {
+      return {
+        'status': true,
+        'data': res.data['data'],
+      };
+    } else {
+      return {'status': false, 'date': [], 'msg': res.data['message']};
+    }
+  }
 }