Bump textual from 0.71.0 to 0.81.0

Bumps [textual](https://github.com/Textualize/textual) from 0.71.0 to 0.81.0.
- [Release notes](https://github.com/Textualize/textual/releases)
- [Changelog](https://github.com/Textualize/textual/blob/main/CHANGELOG.md)
- [Commits](https://github.com/Textualize/textual/commits/v0.81.0)

---
updated-dependencies:
- dependency-name: textual
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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