Only augment `vue`, not sub-packages

### Describe the bug

Issue discussed in [#28542](https://github.com/nuxt/nuxt/pull/28542).
Possibly solves issue in [this comment](https://github.com/nuxt/nuxt/issues/28869#issuecomment-2336835817).

### Reproduction

https://github.com/nuxt/nuxt/pull/28542

### System Info

```Shell
Binaries:
Node: 20.16.0 - ~/.nvm/versions/node/v20.16.0/bin/node
npm: 10.8.1 - ~/.nvm/versions/node/v20.16.0/bin/npm
pnpm: 9.9.0 - ~/repos/qarar/node_modules/.bin/pnpm
Browsers:
Chrome: 128.0.6613.137
```

### Used Package Manager

pnpm

### Additional context

_No response_

### Validations

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