Add plop templates for C++ library creation

[jglanz]

### Description

This pull request introduces plop templates, utilities, and actions to streamline the process of creating new C++ libraries. Key updates include:

- Added templates for library headers, source files, CMake configurations, and test cases under `tools/plop/templates/create-cxx-library/`.
- Implemented utility modules (`plop-constants.js`, `plop-shared-utils.js`) to define constants and shared helper functions.
- Registered shared plop actions in `tools/plop/actions/SharedActions.js`.
- Moved `package.cmake` to `cmake/package.cmake`.

### Related Issues

_No related issues linked._

### Checklist

- [ ] Code compiles, runs, and passes tests on your local machine.
- [ ] Code is formatted appropriately and adheres to project guidelines.
- [ ] Documentation has been updated if applicable.