deps: bump the dependencies-major group across 1 directory with 2 updates

Bumps the dependencies-major group with 2 updates in the / directory: [next](https://github.com/vercel/next.js) and [zod](https://github.com/colinhacks/zod).


Updates `next` from 15.5.3 to 16.0.0
- [Release notes](https://github.com/vercel/next.js/releases)
- [Changelog](https://github.com/vercel/next.js/blob/canary/release.js)
- [Commits](vercel/next.js@v15.5.3...v16.0.0)

Updates `zod` from 3.25.76 to 4.1.12
- [Release notes](https://github.com/colinhacks/zod/releases)
- [Commits](colinhacks/zod@v3.25.76...v4.1.12)

---
updated-dependencies:
- dependency-name: next
  dependency-version: 16.0.0
  dependency-type: direct:production
  update-type: version-update:semver-major
  dependency-group: dependencies-major
- dependency-name: zod
  dependency-version: 4.1.12
  dependency-type: direct:production
  update-type: version-update:semver-major
  dependency-group: dependencies-major
...

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Author: dependabot[bot]