test: verify fs file operations

[f3lixel]

This pull request refactors the project export and package management logic to remove Docker dependencies and operate directly on the filesystem, simplifying the workflow and improving compatibility. Additionally, a new test suite is added to verify file operations outside of Docker.

Refactoring: Remove Docker Dependency and Use Filesystem

• The exportContainerCode function in export.ts is replaced with exportProjectCode, which exports a project by copying files directly from the filesystem and running pnpm build, rather than using Docker commands.
• The addDependency function in package.ts now installs packages using pnpm add directly in the project directory, instead of executing commands inside a Docker container. Also, the dev flag is updated to --save-dev.
• A new buildProject function is added to package.ts to build the project using pnpm build in the specified directory, further removing Docker dependency.

Testing: File Operations Without Docker

• A new test suite is added in file.test.ts to verify file operations such as creating, reading, renaming, removing files, and building file trees, all performed directly on the filesystem without Docker.