Update furo requirement from <2025,>=2024.8.6 to >=2024.8.6,<2026

Updates the requirements on [furo](https://github.com/pradyunsg/furo) to permit the latest version.
- [Release notes](https://github.com/pradyunsg/furo/releases)
- [Changelog](https://github.com/pradyunsg/furo/blob/main/docs/changelog.md)
- [Commits](https://github.com/pradyunsg/furo/compare/2024.08.06...2025.07.19

)

---
updated-dependencies:
- dependency-name: furo
  dependency-version: 2025.7.19
  dependency-type: direct:production
...

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