Now we resolve absolute source url for our preview model, so it
will always find the custom mesh files.
Also always use the Node type preview if the instance is a component,
even if the root node is Model. This ensures the preview works properly
in case there are child nodes inside the component.
Fixes: QDS-6204
Change-Id: I48ef273e5a5dca13abe25816b5edf0be7dd217ff
Reviewed-by: <github-actions-qt-creator@cristianadam.eu>
Reviewed-by: Mahmoud Badri <mahmoud.badri@qt.io>
Reviewed-by: Thomas Hartmann <thomas.hartmann@qt.io>