feat: add support for optional message in expect API

[MangelMaxime]

1. Make build.sh executable
2. Add a name to package.json otherwise the package-lock.json gets changes based on the folder name
3. Add support for optional message in the expect method

[Copilot]

Pull Request Overview

This PR adds support for an optional message parameter to the expect API in the Vitest bindings, along with project configuration improvements. The optional message parameter allows developers to provide custom error messages when assertions fail, enhancing test debugging capabilities.

Key changes:

• Enhanced the expect method signature to accept an optional message parameter
• Added a test case demonstrating the new optional message functionality
• Fixed package.json configuration by adding a stable package name

Reviewed Changes

Copilot reviewed 3 out of 5 changed files in this pull request and generated no comments.

File	Description
src/Vitest/Library.fs	Added optional msg parameter to the expect method signature
tests/Vitest/Program.test.fs	Added test case demonstrating usage of the optional message parameter
package.json	Added package name to stabilize package-lock.json generation

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[Freymaurer]

Thanks for the PR please update src/Vitest/CHANGELOG.md and add your changes to UNRELEASED or tick up the rc by one number if you want it to be released directly 🙂