Update dependency sphinx to v9

renovate[bot] · web-flow · commit c501cd9b096f · 2026-02-27T00:44:42.000Z
diff --git a/pyproject.toml b/pyproject.toml
@@ -46,7 +46,7 @@ pre-commit = "^4.5.1"
 [tool.poetry.group.docs.dependencies]
 doc8 = "^2.0.0"
 furo = "^2025.12.19"
-sphinx = "^8.2.3"
+sphinx = "^9.1.0"
 sphinx-autobuild = "^2025.8.25"
 sphinx-copybutton = "^0.5.2"
 sphinx-design = "^0.7.0"
