When the title is in Chinese, the corresponding varient cannot be searched

### Describe the bug

When the varient title is in Chinese, the corresponding varient cannot be searched

### Reproduction

[When the title is in Chinese, the corresponding varient cannot be searched](https://stackblitz.com/edit/histoire-vue3-starter-bdpjk7?file=src%2FInjectDemo.story.vue)

### System Info

```shell
System:
OS: macOS 13.3.1
CPU: (8) arm64 Apple M1 Pro
Memory: 63.05 MB / 16.00 GB
Shell: 5.9 - /bin/zsh
Binaries:
Node: 18.16.0 - ~/Library/Caches/fnm_multishells/686_1684393930284/bin/node
Yarn: 1.22.19 - ~/Library/Caches/fnm_multishells/686_1684393930284/bin/yarn
npm: 9.6.6 - ~/Library/Caches/fnm_multishells/686_1684393930284/bin/npm
Browsers:
Chrome: 112.0.5615.137
Safari: 16.4
```

### Used Package Manager

pnpm

### Validations

- [X] Follow our [Code of Conduct](https://github.com/histoire-dev/histoire/blob/main/CODE_OF_CONDUCT.md)
- [X] Read the [Contributing Guidelines](https://github.com/histoire-dev/histoire/blob/main/CONTRIBUTING.md).
- [X] Read the [docs](https://histoire.dev/guide/).
- [X] Check that there isn't [already an issue](https://github.com/histoire-dev/histoire/issues) that reports the same bug to avoid creating a duplicate.
- [X] Check that this is a concrete bug. For Q&A open a [GitHub Discussion](https://github.com/histoire-dev/histoire/discussions).
- [X] The provided reproduction is a [minimal reproducible example](https://stackoverflow.com/help/minimal-reproducible-example) of the bug.

Start with the linked StackBlitz reproduction, especially src/InjectDemo.story.vue, and inspect the search behavior for Chinese variant titles. Trace the relevant search entry point and add a regression test for matching the corresponding variant; done when the Chinese-titled variant is searchable.

Written by the indexing model from the issue text.