chore(deps): bump the python group with 7 updates

Bumps the python group with 7 updates:

| Package | From | To |
| --- | --- | --- |
| [websockets](https://github.com/python-websockets/websockets) | `16.0` | `16.1` |
| [prek](https://github.com/j178/prek) | `0.4.8` | `0.4.9` |
| [mypy](https://github.com/python/mypy) | `2.1.0` | `2.2.0` |
| [ruff](https://github.com/astral-sh/ruff) | `0.15.20` | `0.15.21` |
| [types-docutils](https://github.com/python/typeshed) | `0.22.3.20260518` | `0.22.3.20260712` |
| [shibuya](https://github.com/lepture/shibuya) | `2026.5.19` | `2026.7.12` |
| [sphinxcontrib-mermaid](https://github.com/mgaitan/sphinxcontrib-mermaid) | `2.0.2` | `2.0.3` |


Updates `websockets` from 16.0 to 16.1
- [Release notes](https://github.com/python-websockets/websockets/releases)
- [Commits](python-websockets/websockets@16.0...16.1)

Updates `prek` from 0.4.8 to 0.4.9
- [Release notes](https://github.com/j178/prek/releases)
- [Changelog](https://github.com/j178/prek/blob/master/CHANGELOG.md)
- [Commits](j178/prek@v0.4.8...v0.4.9)

Updates `mypy` from 2.1.0 to 2.2.0
- [Changelog](https://github.com/python/mypy/blob/master/CHANGELOG.md)
- [Commits](python/mypy@v2.1.0...v2.2.0)

Updates `ruff` from 0.15.20 to 0.15.21
- [Release notes](https://github.com/astral-sh/ruff/releases)
- [Changelog](https://github.com/astral-sh/ruff/blob/main/CHANGELOG.md)
- [Commits](astral-sh/ruff@0.15.20...0.15.21)

Updates `types-docutils` from 0.22.3.20260518 to 0.22.3.20260712
- [Commits](https://github.com/python/typeshed/commits)

Updates `shibuya` from 2026.5.19 to 2026.7.12
- [Release notes](https://github.com/lepture/shibuya/releases)
- [Changelog](https://github.com/lepture/shibuya/blob/main/docs/changelog.rst)
- [Commits](lepture/shibuya@2026.5.19...2026.7.12)

Updates `sphinxcontrib-mermaid` from 2.0.2 to 2.0.3
- [Changelog](https://github.com/mgaitan/sphinxcontrib-mermaid/blob/master/CHANGELOG.md)
- [Commits](mgaitan/sphinxcontrib-mermaid@2.0.2...v2.0.3)

---
updated-dependencies:
- dependency-name: websockets
  dependency-version: '16.1'
  dependency-type: direct:production
  update-type: version-update:semver-minor
  dependency-group: python
- dependency-name: prek
  dependency-version: 0.4.9
  dependency-type: direct:development
  update-type: version-update:semver-patch
  dependency-group: python
- dependency-name: mypy
  dependency-version: 2.2.0
  dependency-type: direct:development
  update-type: version-update:semver-minor
  dependency-group: python
- dependency-name: ruff
  dependency-version: 0.15.21
  dependency-type: direct:development
  update-type: version-update:semver-patch
  dependency-group: python
- dependency-name: types-docutils
  dependency-version: 0.22.3.20260712
  dependency-type: direct:development
  update-type: version-update:semver-patch
  dependency-group: python
- dependency-name: shibuya
  dependency-version: 2026.7.12
  dependency-type: direct:development
  update-type: version-update:semver-minor
  dependency-group: python
- dependency-name: sphinxcontrib-mermaid
  dependency-version: 2.0.3
  dependency-type: direct:development
  update-type: version-update:semver-patch
  dependency-group: python
...

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Author: dependabot[bot]