NgbOffcanvasRef and NgbModalRef should expose a ComponentRef

Bug description:

NgbOffcanvasRef and NgbModalRef should expose a ComponentRef when using a component type as content. Currently the NgbOffcanvasRef exposes a componentInstance. This makes it hard to use components with Signal inputs, as you cannot do myComponentInstance.myProp = value. Instead, the proper way is to use the function setInput on a componentRef. setInput also triggers change detection and ngOnChanges correctly.

Link to minimally-working StackBlitz that reproduces the issue:

https://stackblitz.com/edit/angular-5zsark-l3yj9i

Versions of Angular, ng-bootstrap and Bootstrap:

Angular: 17.3.1

ng-bootstrap: 16.0.0

Bootstrap: 5.3.3