Label having the same name with variables caused `SyntaxError: Unexpected token ':'`

Here's my [repo for reproduction](https://github.com/qwertycxz/claude-agent-acp/tree/oxc-bug). It used **Vitest**.

1. Git clone the `oxc-bug` branch.
2. `npm i`
3. `npm run test`

Then, all test failed as in the [GitHub Action](https://github.com/qwertycxz/claude-agent-acp/actions/runs/25842318976).