Bump furo from 2025.7.19 to 2025.9.25

Bumps [furo](https://github.com/pradyunsg/furo) from 2025.7.19 to 2025.9.25.
- [Release notes](https://github.com/pradyunsg/furo/releases)
- [Changelog](https://github.com/pradyunsg/furo/blob/main/docs/changelog.md)
- [Commits](pradyunsg/furo@2025.07.19...2025.09.25)

---
updated-dependencies:
- dependency-name: furo
  dependency-version: 2025.9.25
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

pyproject.toml

@@ -35,7 +35,7 @@ Documentation = "https://flogin.readthedocs.io/en/latest/"
 [project.optional-dependencies]
 docs = [
     "sphinx>=7.0.0,<9.0.0",
-    "furo==2025.7.19", # theme // https://pradyunsg.me/furo/customisation/announcement/
+    "furo==2025.9.25", # theme // https://pradyunsg.me/furo/customisation/announcement/
     "sphinx-toolbox>=3.5,<5.0",  # https://sphinx-toolbox.readthedocs.io/en/latest/extensions/index.html
     "sphinxcontrib-trio==1.1.2",
     "sphinx-copybutton==0.5.2",