Bump @keystatic/core from 0.5.51 to 0.6.6 in the keystatic group

Bumps the keystatic group with 1 update: [@keystatic/core](https://github.com/Thinkmill/keystatic/tree/HEAD/packages/keystatic).


Updates `@keystatic/core` from 0.5.51 to 0.6.6
- [Changelog](https://github.com/Thinkmill/keystatic/blob/main/packages/keystatic/CHANGELOG.md)
- [Commits](https://github.com/Thinkmill/keystatic/commits/@keystatic/core@0.6.6/packages/keystatic)

---
updated-dependencies:
- dependency-name: "@keystatic/core"
  dependency-version: 0.6.6
  dependency-type: direct:production
  update-type: version-update:semver-minor
  dependency-group: keystatic
...

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Author: dependabot[bot]