Implement request-responses protocols (#6634)

* Implement request-responses protocols

* Add tests

* Fix sc-cli

* Apply suggestions from code review

Co-authored-by: Max Inden <[email protected]>

* Fix naming

* Fix other issues

* Other naming fix

* Fix error logging

* Max sizes to u64

* Don't kill connections on refusal to process

* Adjust comment

Co-authored-by: Max Inden <[email protected]>