chore: add OpenAPI 3.0.x interface

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Latest commit: 7b9ed36768c0560c4bd3155036d0fcc068334c89

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Name	Status	Preview	Comments	Updated (UTC)
hey-api-docs	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Nov 2, 2024 10:50pm

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Codecov Report

Attention: Patch coverage is 96.29630% with 1 line in your changes missing coverage. Please review.

Project coverage is 73.19%. Comparing base (2d52fd0) to head (7b9ed36). Report is 2 commits behind head on main.

Files with missing lines	Patch %	Lines
.../openapi-ts/src/plugins/@hey-api/schemas/plugin.ts	91.66%	1 Missing :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #1225 +/- ## ======================================= Coverage 73.19% 73.19% ======================================= Files 127 127 Lines 17706 17706 Branches 1732 1732 ======================================= Hits 12960 12960 Misses 4743 4743 Partials 3 3 ``` | [Flag](https://app.codecov.io/gh/hey-api/openapi-ts/pull/1225/flags?src=pr&el=flags&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=hey-api) | Coverage Δ | | |---|---|---| | [unittests](https://app.codecov.io/gh/hey-api/openapi-ts/pull/1225/flags?src=pr&el=flag&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=hey-api) | `73.19% <96.29%> (ø)` | | Flags with carried forward coverage won't be shown. [Click here](https://docs.codecov.io/docs/carryforward-flags?utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=hey-api#carryforward-flags-in-the-pull-request-comment) to find out more.

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