Easier Graph Construction Tools

[Dalouvid]

Hey guys, please add a function that simplifies the construction of graphs from pure text.

A possible solution would be to use the LangChain GraphDocuments Object and provide a way to translate that to a Kùzu Graph, like it is done here. Adding a LangChain GraphDocument would then simply be "KuzuGraph.add_graph_documents(graph_documents)"

I think that offering a better way to build Kùzu graphs using LangChain could attract many new users.

Thank you guys for your awesome work! Cheers, David