Use Protobuf message replace Object and implement all hessian type

C++ does not have a global parent like Java Object, so there is no single type that can represent all hessian types, so we create an Object base class from which all hessian types are inherited. However, this Object is still not easy to use, complex to construct, and does not provide a complete API similar to that of a standard container. If we use Protobuf to define all Hessian types and use the ProtoBuf Message Object as our base Object class, we can reuse the entire Protobuf API that we provide, thus improving the overall usability.

No files, tests, or entry points are named in the issue. Start by locating the existing Object base class and Hessian type definitions, then determine the Protobuf model and API coverage needed for all Hessian types to use a Protobuf Message as their base object.

Written by the indexing model from the issue text.