feat: change scale limits

zooming in a lot is sometimes useful,
but zooming out is basically useless and annoying
(when you want to put it back to covering the full window)

if you really need to zoom out, you can always resize the window

src/main.rs

@@ -42,6 +42,8 @@ impl State {
             if let Some(allocation) = self.image_display.as_ref() {
                 widget::image::viewer(allocation.handle().clone())
                     .filter_method(self.image_filter)
+                    .max_scale(50.)
+                    .min_scale(1.)
                     .width(Length::Fill)
                     .height(Length::Fill)
                     .into()