fix: add cue definitions for embedded types

This change refactors some embedded types within existing
definitions into definitions themselves.

This provides a pathway to much better go types being generated
by `make cuegen` and solving some of the pain observed in
https://github.com/revanite-io/pvtr-github-repo/blob/main/evaluation_plans/reusable_steps/evaluations_test.go#L21

Signed-off-by: Travis Truman <trumant@gmail.com>

Author: trumant