[GIE-SDK] Implement the client-side SDK on GAIA for end-users

This is an important feature requested to replace the legacy GIE engine MaxGraph with GAIA. Here, SDK is simply a set of client APIs for end-users to easily interact with the GIE engines by sending query requests and receiving query results. We may take into consideration the legacy SDK of MG as well as possible future integration with GraphScope's coordinator.