refactor: remove NestJS and Express example applications

- Deleted the entire NestJS application including its configuration files, source code, and package dependencies.
- Removed the Express application configuration and TypeScript settings.
- Cleaned up project management module by deleting its source files, configuration, and changelog.
- Updated package-lock.json to reflect the removal of the above applications and their dependencies.
- Added a new server package with a basic NestJS setup and integrated ObjectQL.
- Introduced new project management features and updated related configurations.

Author: hotlong