Implement Checkpointer for DynamoDB

[jdbaker01]

Implement the checkpoint interface in langchain (https://langchain-ai.github.io/langgraph/how-tos/persistence/?ref=blog.langchain.dev) for DynamoDB. This should include both checkpoint and memory store.

[jdbaker01]

For first time contributors interested in taking up this feature, I am available to assist with the design and mentoring as part of you taking up the development task.

[zhaoJoseph]

Hi, me and a team of 4 from University of Toronto are interested in this feature. Can this task be finished in a couple of weeks?

[Pierozi]

I'm not sure if this feature should be included here as it concern Langgraph package.
@zhaoJoseph look at the postgres one if you are interested to contribute https://github.com/langchain-ai/langgraph/tree/main/libs/checkpoint-postgres

it's quite a simple task, but you must have good DynamoDB access pattern knowledge to properly use the primary keys.

[zhaoJoseph]

Thanks for the clarification and guidance. I am also confused why this is under langchain-aws, also a maintainer from langgraph stated that they are only providing implementations for partner providers. langchain-ai/langgraph#1351, thanks anyway.