feat(experimental): allow disabling the module runner

[sheremet-va]

Description

Resolves #7234
Resolves #9181

TODO

• Fix issues on Windows
• Seems like tests in core hang even when this flag is not used 🤔

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[hi-ogawa]

Can you add some mock tests to show what working and not working? Also it's nice to have a failing test case (like relative ./basic import instead ./basic.js), which would pass if it were module runner.

[sheremet-va]

Can you add some mock tests to show what working and not working? Also it's nice to have a failing test case (like relative ./basic import instead ./basic.js), which would pass if it were module runner.

I didn't implement mocking yet, there will be a separate project in examples when this is ready

[Copilot]

Pull request overview

This PR introduces experimental support for disabling Vite's module runner and falling back to native Node.js import. This allows tests to run in their actual environment without Vite's transformation layer, which is beneficial for backend Node.js code that doesn't require transformations.

Key changes:

• Added experimental.viteModuleRunner (default: true) and experimental.nodeLoader (default: true) configuration options
• Implemented native module runner using Node.js Loaders API (requires Node 22.15+)
• Refactored mocking system to support both Vite module runner and native imports
• Updated error messages to remove quotes around file paths for consistency

Reviewed changes

Copilot reviewed 99 out of 101 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
packages/vitest/src/utils/nativeModuleRunner.ts	New native module runner implementation that uses native imports
packages/vitest/src/runtime/workers/native.ts	Node.js loader hooks implementation for transforms when module runner is disabled
packages/vitest/src/runtime/moduleRunner/nativeModuleMocker.ts	Native mocker implementation using Node.js module hooks
packages/vitest/src/runtime/moduleRunner/bareModuleMocker.ts	Base mocker class extracted from VitestMocker
packages/mocker/src/node/parsers.ts	New module export parser using es-module-lexer and cjs-module-lexer
packages/mocker/src/node/hoistMocks.ts	Extracted hoisting logic from plugin
test/cli/test/no-module-runner.test.ts	Comprehensive test suite for native module runner
examples/native/	Complete example project demonstrating native module runner usage
docs/config/experimental.md	Documentation for new experimental features

Files not reviewed (1)

• pnpm-lock.yaml: Language not supported