L2 Constructs for AWS Elemental MediaLive

## Description

Issue ticket for tracking AWS Elemental MediaLive L2 Design and implementation.

## Roles

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

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

## Workflow

- [x] Tracking issue created (label: `status/proposed`)
- [ ] API bar raiser assigned (ping us at [#aws-cdk-rfcs](https://cdk-dev.slack.com/archives/C025ZFGMUCD) if needed)
- [ ] Kick off meeting
- [ ] RFC pull request submitted (label: `status/review`)
- [ ] Community reach out (via Slack and/or Twitter)
- [ ] API signed-off (label `status/api-approved` applied to pull request)
- [ ] 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 linked RFC Process and the workflow checklist; this issue names no implementation files, tests, or entry point. Define and document the AWS Elemental MediaLive L2 design, then progress the checklist through RFC review and implementation completion.

Written by the indexing model from the issue text.