Currently, Millumin only displays a confirmation dialog when closing a project that contains unsaved changes. If the project has already been saved, the application closes immediately without any warning.

It would be helpful to add an optional confirmation dialog when closing Millumin while one or more outputs are active, even if there are no unsaved changes.

This would help prevent accidentally closing the application during rehearsals or live shows, where an active output is still sending content. In these situations, an unintended application quit can immediately interrupt the show.

Suggested behavior:

If there are unsaved changes, keep the current confirmation dialog.
If there are no unsaved changes but at least one output is active, display a confirmation such as:

"One or more outputs are currently active. Are you sure you want to quit Millumin?"

If no outputs are active and there are no unsaved changes, close immediately as it does today.
Optionally, make this behavior configurable in Preferences so users can enable or disable the warning.

This small addition would provide an extra layer of protection against accidental application closure during live operation without affecting the normal workflow.