Add GitHub Actions workflow for automated testing (#15)

[mattfsourcecode]

Overview of the Workflow

This GitHub Actions workflow automates the testing of the fastify-swc-server CLI by installing the npm package and executing its bin script as if it were installed directly from the npm registry. This ensures the package performs as expected in a real-world usage scenario before pull requests are merged. The process includes validating the package's functionality, enabling compatibility with HTTPS for repository access, and addressing a required Node.js version upgrade.

The workflow performs the following steps:

1. Checkout Code: The latest code is checked out from the repository using the actions/checkout action.
2. Configure Git for HTTPS: The workflow configures Git to use HTTPS as the default method for cloning repositories.
3. Validate Git Connection: A test is run to validate the Git connection using HTTPS, ensuring that the repository can be accessed without SSH keys.
4. Set up pnpm: The pnpm package manager is set up with a specific version to handle dependency installation and management.
5. Set up Node.js: The workflow installs Node.js (version lts/*), ensuring compatibility with the latest features and dependencies.
6. Install Dependencies: Dependencies are installed using pnpm, while skipping the prepare script to prevent issues during installation.
7. Pack and Install CLI: The workflow uses npm pack to package the CLI and installs it globally, verifying that the fastify-swc-server bin script works as expected.
8. Test CLI Functionality: A test project is generated using the CLI, dependencies are installed, and the project is built and run in development mode. The server is then verified by making a request to the default URL.

These additional changes were required for the completion of the workflow:

• Transitions the git clone command executed in the bin script to support HTTPS
• Upgrades the minimum Node.js version requirement to v20

This setup supports a process where a version bump is the last change merged before the updated version is published to npm. This final step adds an additional layer of validation to ensure that the npm package, including any version updates, functions correctly. By testing the package’s functionality in the CI/CD pipeline, it confirms the integrity of the package and verifies that it works as intended before being made publicly available.

Closes #15