Confirm before closing scene and application

[Anthony-Gaudino]

When attempting to close a newly created or modified scene without saving, the user should receive a warning through a confirmation pop-up or a similar prompt.

Similarly, if the user intends to exit the application with unsaved scenes or changes, a warning should be triggered, prompting the user to confirm their action.

[turanszkij]

I don't want to have this for now.