deps(docs): update docusaurus monorepo to v3.9.1 (#956)

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This PR contains the following updates:

| Package | Change | Age | Confidence |
|---|---|---|---|
| [@docusaurus/core](https://redirect.github.com/facebook/docusaurus)
([source](https://redirect.github.com/facebook/docusaurus/tree/HEAD/packages/docusaurus))
| [`3.9.0` ->
`3.9.1`](https://renovatebot.com/diffs/npm/@docusaurus%2fcore/3.9.0/3.9.1)
|
[![age](https://developer.mend.io/api/mc/badges/age/npm/@docusaurus%2fcore/3.9.1?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![confidence](https://developer.mend.io/api/mc/badges/confidence/npm/@docusaurus%2fcore/3.9.0/3.9.1?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
|
[@docusaurus/module-type-aliases](https://redirect.github.com/facebook/docusaurus)
([source](https://redirect.github.com/facebook/docusaurus/tree/HEAD/packages/docusaurus-module-type-aliases))
| [`3.9.0` ->
`3.9.1`](https://renovatebot.com/diffs/npm/@docusaurus%2fmodule-type-aliases/3.9.0/3.9.1)
|
[![age](https://developer.mend.io/api/mc/badges/age/npm/@docusaurus%2fmodule-type-aliases/3.9.1?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![confidence](https://developer.mend.io/api/mc/badges/confidence/npm/@docusaurus%2fmodule-type-aliases/3.9.0/3.9.1?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
|
[@docusaurus/preset-classic](https://redirect.github.com/facebook/docusaurus)
([source](https://redirect.github.com/facebook/docusaurus/tree/HEAD/packages/docusaurus-preset-classic))
| [`3.9.0` ->
`3.9.1`](https://renovatebot.com/diffs/npm/@docusaurus%2fpreset-classic/3.9.0/3.9.1)
|
[![age](https://developer.mend.io/api/mc/badges/age/npm/@docusaurus%2fpreset-classic/3.9.1?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![confidence](https://developer.mend.io/api/mc/badges/confidence/npm/@docusaurus%2fpreset-classic/3.9.0/3.9.1?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
|
[@docusaurus/theme-mermaid](https://redirect.github.com/facebook/docusaurus)
([source](https://redirect.github.com/facebook/docusaurus/tree/HEAD/packages/docusaurus-theme-mermaid))
| [`3.9.0` ->
`3.9.1`](https://renovatebot.com/diffs/npm/@docusaurus%2ftheme-mermaid/3.9.0/3.9.1)
|
[![age](https://developer.mend.io/api/mc/badges/age/npm/@docusaurus%2ftheme-mermaid/3.9.1?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![confidence](https://developer.mend.io/api/mc/badges/confidence/npm/@docusaurus%2ftheme-mermaid/3.9.0/3.9.1?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
| [@docusaurus/types](https://redirect.github.com/facebook/docusaurus)
([source](https://redirect.github.com/facebook/docusaurus/tree/HEAD/packages/docusaurus-types))
| [`3.9.0` ->
`3.9.1`](https://renovatebot.com/diffs/npm/@docusaurus%2ftypes/3.9.0/3.9.1)
|
[![age](https://developer.mend.io/api/mc/badges/age/npm/@docusaurus%2ftypes/3.9.1?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![confidence](https://developer.mend.io/api/mc/badges/confidence/npm/@docusaurus%2ftypes/3.9.0/3.9.1?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|

---

### Release Notes

<details>
<summary>facebook/docusaurus (@&#8203;docusaurus/core)</summary>

###
[`v3.9.1`](https://redirect.github.com/facebook/docusaurus/releases/tag/v3.9.1):
3.9.1

[Compare
Source](https://redirect.github.com/facebook/docusaurus/compare/v3.9.0...v3.9.1)

#### 3.9.1 (2025-09-26)

##### 🐛 Bug Fix

- `docusaurus`
-
[#&#8203;11434](https://redirect.github.com/facebook/docusaurus/pull/11434)
fix(core): fix Docusaurus outDir for sites using baseUrl
([@&#8203;slorber](https://redirect.github.com/slorber))

##### Committers: 1

- Sébastien Lorber
([@&#8203;slorber](https://redirect.github.com/slorber))

</details>

<details>
<summary>facebook/docusaurus
(@&#8203;docusaurus/module-type-aliases)</summary>

###
[`v3.9.1`](https://redirect.github.com/facebook/docusaurus/compare/v3.9.0...c0dd59f0e712f85b6053c59e46b0514b5d2d1414)

[Compare
Source](https://redirect.github.com/facebook/docusaurus/compare/v3.9.0...v3.9.1)

</details>

<details>
<summary>facebook/docusaurus
(@&#8203;docusaurus/preset-classic)</summary>

###
[`v3.9.1`](https://redirect.github.com/facebook/docusaurus/compare/v3.9.0...c0dd59f0e712f85b6053c59e46b0514b5d2d1414)

[Compare
Source](https://redirect.github.com/facebook/docusaurus/compare/v3.9.0...v3.9.1)

</details>

<details>
<summary>facebook/docusaurus
(@&#8203;docusaurus/theme-mermaid)</summary>

###
[`v3.9.1`](https://redirect.github.com/facebook/docusaurus/blob/HEAD/CHANGELOG.md#391-2025-09-26)

[Compare
Source](https://redirect.github.com/facebook/docusaurus/compare/v3.9.0...v3.9.1)

##### 🐛 Bug Fix

- `docusaurus`
-
[#&#8203;11434](https://redirect.github.com/facebook/docusaurus/pull/11434)
fix(core): fix Docusaurus outDir for sites using baseUrl
([@&#8203;slorber](https://redirect.github.com/slorber))

##### Committers: 1

- Sébastien Lorber
([@&#8203;slorber](https://redirect.github.com/slorber))

</details>

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