CDK Comprehensive Validation

## Description

Shift left failures that occur during AWS CloudFormation deployment

## Roles

| Role | User
|---------------------|------------------------------
| Proposed by | @conroyka
| Author(s) | @conroyka
| API Bar Raiser | @rix0rrr
| Stakeholders |

> See [RFC Process](https://github.com/aws/aws-cdk-rfcs#rfc-process) for details

## Workflow

- [x] Tracking issue created (label: `status/proposed`)
- [x] API bar raiser assigned (ping us at [#aws-cdk-rfcs](https://cdk-dev.slack.com/archives/C025ZFGMUCD) if needed)
- [x] Kick off meeting
- [x] RFC pull request submitted (label: `status/review`)
- [x] Community reach out (via Slack and/or Twitter)
- [x] API signed-off (label `status/api-approved` applied to pull request)
- [x] Final comments period (label: `status/final-comments-period`)
- [ ] Approved and merged (label: `status/approved`)
- [ ] Execution plan submitted (label: `status/planning`)
- [ ] Plan approved and merged (label: `status/implementing`)
- [ ] Implementation complete (label: `status/done`)

---

> Author is responsible to progress the RFC according to this checklist, and
apply the relevant labels to this issue so that the RFC table in README gets
updated.

Start with the RFC Process linked in the issue and review the completed workflow, especially the submitted RFC pull request and API sign-off. The scope is to define comprehensive validation that shifts failures earlier than AWS CloudFormation deployment; completion follows the remaining approval, execution-plan, implementation, and done milestones.

Written by the indexing model from the issue text.