Split out all AWS-related files into a aws-core or similar package

**What I'd like:**
It would be lovely if all of the settings, templates and files that are rendered in to make this compatible with EKS/AWS auth could be split into a separate package that you pull in into the variants explicitly.
I have so far found AWS-specific things in core packages, such as:
- release
- kubernetes (also not very clear that this is EKS-D unless you look pretty deep)

(non-exhaustive list)

Start by inventorying the AWS-specific settings, templates, and rendered files in the release and kubernetes packages, including the EKS-D-related paths. Trace how variants currently include them, then define the package boundary and verify that AWS/EKS variants explicitly pull it in without affecting non-AWS variants.

Written by the indexing model from the issue text.