Durable streams

[maxdml]

Implement the durable streams API as implemented in other Transact SDKs

dbos-inc/dbos-transact-py#420

[AayushSaini101]

would like to work on this @maxdml

[maxdml]

Hi @AayushSaini101, thanks! Make sure to check how the python implementation looks like, and feel free to get in touch about particulars of the design. Discord is a good place for this!