Feature Request and Contribution Offer: Arkflow S3 & SQL Output

Hello,

I hope you're doing well.
I wanted to ask if you have any plans to add S3 or SQL as output options in Arkflow.
If so, I’d love to contribute by developing those features myself. Although my knowledge of Rust and the Arkflow engine is still limited, I’m eager to learn and get involved.

I’m not sure exactly when I’ll be able to complete the features, but I’d prefer to implement them one at a time and get your feedback through PRs as I go. If you’re open to it, I’d be happy to start working on it.

No files, tests, or entry points are named. Start by confirming whether S3 or SQL output is the priority and defining the supported backends and acceptance criteria with maintainers. Done would require an agreed design and a reviewed contribution for the selected output option.

Written by the indexing model from the issue text.