AWS: add tool to cleanup packages (and package parameters)

helix-pages creates a new package for each deployment (until we have a proper helix-pages service).
this also creates a set of package params, which clutter the function and parameters store.

every CI run (smoke tests, etc) create a new package - which is quite a lot.

there should be a tool that can cleanup packages.

No file, test, or CLI entry point is named. Start by locating the AWS deployment and package-management entry points, then trace how helix-pages creates packages and package parameters. Done should be a tool that cleans up the unwanted packages and associated parameters, with coverage for the cleanup behavior.

Written by the indexing model from the issue text.