Describe the bug

When upgrading from vitest 2.0.5 to 2.1.2, something has changed with the types for custom test contexts (export const myTest = test.extend(...)) that results in tsc reporting all test function parameters as having any type, when it previously used to be able to identify their types. An example error:

src/utils/useFrozenState.test.ts:41:63 - error TS7006: Parameter 'initialState' implicitly has an 'any' type.

41     it.each([null, undefined])("refuses to freeze %o", async (initialState) => {
                                                                 ~~~~~~~~~~~~

In this case, it should be able to tell that initialState has a type of null | undefined. Vitest was the only library changed, and reverting back to 2.0.5 restores the prior behavior where types were identified correctly.

Reproduction

Our repository is set up similar to this arrangement: https://github.com/qidydl/vite-workspace-experiment where we use paths and references in tsconfig.json to refer to shared code. The test context in the shared code is not complex:

export interface CustomTestContext {
    user: UserEvent;
}

export const customTest = test.extend<CustomTestContext>({
    user: async ({}, use) => await use(userEvent.setup()),
});

The usage is also not complex:

import { customTest as it } from "@shared/_test/testUtils";

it.each([null, undefined])("refuses to freeze %o", async (initialState) => {
    ...test using initialState
});

System Info

System:
    OS: Windows 11 10.0.22631
    CPU: (32) x64 13th Gen Intel(R) Core(TM) i9-13950HX
    Memory: 13.43 GB / 31.61 GB
  Binaries:
    Node: 20.18.0 - C:\Program Files\nodejs\node.EXE
    npm: 10.8.2 - C:\Program Files\nodejs\npm.CMD
    pnpm: 9.12.1 - C:\Program Files\nodejs\pnpm.CMD
  Browsers:
    Edge: Chromium (127.0.2651.74)
    Internet Explorer: 11.0.22621.3527
  npmPackages:
    @vitest/coverage-istanbul: ^2.1.2 => 2.1.2
    @vitest/eslint-plugin: ^1.1.7 => 1.1.7
    @vitest/ui: ^2.1.2 => 2.1.2
    vite: ^5.4.8 => 5.4.8
    vitest: ^2.1.2 => 2.1.2

Used Package Manager

pnpm

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