feat: add typings and interfaces for Overlay Specification v1.0.0

[jeremyfiel]

related #1246

What/Why/How?

Provides typings and interfaces for a structured Overlay description per the https://github.com/OAI/Overlay-Specification

Hopefully this is the first step to providing support for this new specification!

Can't wait to see what you build!

Reference

https://github.com/OAI/Overlay-Specification/releases/tag/1.0.0

Testing

Screenshots (optional)

Check yourself

• [ ] Code changed? - Tested with redoc/reference-docs/workflows (internal)
• [ ] All new/updated code is covered with tests
• [ ] New package installed? - Tested in different environments (browser/node)

Security

• [X] Security impact of change has been considered
• [X] Code follows company security practices and guidelines

[changeset-bot[bot]]

🦋 Changeset detected

Latest commit: 99d425c935c7f54130f0b5aacb91e157ac0ec0f6

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 2 packages

Name	Type
@redocly/openapi-core	Minor
@redocly/cli	Minor

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[jeremyfiel]

thanks for review. I actually missed using the defined NodeType references, so I updated those.