Make worldTransform available on frontend

The world transform of an entity is calculated on the backend, but may still be of use on the frontend. This can be achieved by adding a new component that exposes the worldTransform of its entity from the backend to the frontend or by adding a "worldTransform" or "calculatedWorldTransform" function on QTransform in addition to a boolean "trackWorldTransform" property that enables the feature.

This is related to deprecating viewMatrix on the QCamera class, which is now wrong. The viewMatrix can be calculated by using the world transform and QMatrix4x4::lookAt: https://codereview.qt-project.org/#/c/217106/