Shell completion after unexpected word messes up the prompt

When I attempt to perform shell completion after an unexpected word in an argument with `mise`, the verbose error message from usage messes up the shell prompt.

For example:

```sh
$ mise help Error: × unexpected word: help

mise
```

After pressing typing `mise help` and pressing tab, a multi-row error message is printed, and the prompt, including the current input, becomes garbled and overwritten. This makes it really hard to figure out what's already typed and what's new.