Make the interface of common.sql DBApiHook type-defined

### Body

The current interface of DBApiHook is well described now in the ADR https://github.com/apache/airflow/blob/main/airflow/providers/common/sql/doc/adr/0002-return-common-data-structure-from-dbapihook-derived-hooks.md - but it's not enforced. We should see if we can use Python typing (or posibly other mechanisms) to make the interfaced more stable and enforced. That also includes review of the common.sql API now captured in the .pyi interface (but likely somewhat not complete/broken) which we created in order to make the common.sql API stable.

That needs a new ADR describing it as well.

That is pretty related and should bring `common.sql` API to the level it should have from the very beginning, hopefully becoming a "golden standard" for other common interfaces we expose to our providers.

cc: @bolkedebruin @Taragolis

### Committer

- [X] I acknowledge that I am a maintainer/committer of the Apache Airflow project.