Setting duration to 0 should disable animation

It would be useful if when a progress bar has a duration = 0, then animation would be disabled.

I understand that it may be possible to address this with `.set()` vs `.animate()` - but unfortunately, my use case doesn't allow for this...

No source file or test is named in the issue. Start by locating how the progress bar's duration is handled and how animate() is selected; confirm that a duration of 0 disables animation while preserving the requested progress behavior, then run the relevant existing checks if available.

Written by the indexing model from the issue text.