refacto: RenderingEngine::get_scene_manager() is now not callable from singleton

refacto: RenderingEngine::get_scene_manager() is now not callable from singleton

This permits to make evidence that we have some bad object passing on various code parts. I fixed majority of them to reduce the scope of passed objects

Unfortunately, for some edge cases i should have to expose ISceneManager from client, this should be fixed in the future when our POO will be cleaner client side (we have a mix of rendering and processing in majority of the client objects, it works but it's not clean)