feat: TCP协议支持protobuf序列化，保留JSON兼容

- 新增 tcp_messages_pb2.py protobuf Python绑定
- msg_handler.cpp: 新增 make_packet_pb/raw bytes打包, parse_packet_raw/raw解析
- archery_netcore.cpp: 注册 make_packet_pb/parse_packet_raw
- network.py: 新增 _use_proto 标志，_make_send_packet/_parse_recv 自动选择proto/JSON
- 登录version加+proto后缀标识proto模式
- protobuf序列化/反序列化失败时自动回退JSON

cpp_ext/archery_netcore.cpp

@@ -56,10 +56,17 @@ PYBIND11_MODULE(archery_netcore, m) {
     m.def("make_packet", &netcore::make_packet,
           "Pack TCP packet: header (len+type+checksum) + JSON body",
           py::arg("msg_type"), py::arg("body_dict"));
-    
+
+    m.def("make_packet_pb", &netcore::make_packet_pb,
+          "Pack TCP packet: header (len+type+checksum) + raw bytes body (for protobuf)",
+          py::arg("msg_type"), py::arg("body_bytes"));
+
     m.def("parse_packet", &netcore::parse_packet,
           "Parse TCP packet, return (msg_type, body_dict)");
 
+    m.def("parse_packet_raw", &netcore::parse_packet_raw,
+          "Parse TCP packet, return (msg_type, body_bytes) without JSON parsing");
+
     m.def("get_config", &get_config, "Get system configuration");
 
     m.def(