### What does this PR do?
This PR adds builtin YAML parsing with `Bun.YAML.parse`
```js
import { YAML } from "bun";
const items = YAML.parse("- item1");
console.log(items); // [ "item1" ]
```
Also YAML imports work just like JSON and TOML imports
```js
import pkg from "./package.yaml"
console.log({ pkg }); // { pkg: { name: "pkg", version: "1.1.1" } }
```
### How did you verify your code works?
Added some tests for YAML imports and parsed values.
---------
Co-authored-by: Claude Bot <claude-bot@bun.sh>
Co-authored-by: Claude <noreply@anthropic.com>
Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>
Co-authored-by: Jarred Sumner <jarred@jarredsumner.com>
