Use circle gizmos for capsule (#15602)

# Objective

- The capsule gizmo uses straight lines for the upper and lower circle
which looks pretty ugly.

## Solution

- Use the circle gizmo instead

---

## Showcase

**BEFORE**

![3d_gizmos_sy3CmKUvKO](https://github.com/user-attachments/assets/be014de4-751e-4b40-b814-b5b97bb72031)

**AFTER**

![3d_gizmos_nyADBAUJHg](https://github.com/user-attachments/assets/539ff765-f9d8-4afe-9ac6-41fe83e94e94)

(the circles are red for demonstration purposes only)

# Notes

I also tried using 3d arcs instead of circles but it looks like arcs
need a lot more computation for an almost identical end result. Circles
seem much simpler. The only thing I'm unsure about is if the rotation
stuff is correct. It worked in my testing though.

crates/bevy_gizmos/src/primitives/dim3.rs

@@ -563,11 +563,20 @@ where
                 .short_arc_3d_between(lower_center, start, lower_apex, self.color);
         });
 
-        let upper_lines = upper_points.windows(2).map(|win| (win[0], win[1]));
+        let circle_rotation = self
-        let lower_lines = lower_points.windows(2).map(|win| (win[0], win[1]));
+            .isometry
-        upper_lines.chain(lower_lines).for_each(|(start, end)| {
+            .rotation
-            self.gizmos.line(start, end, self.color);
+            .mul_quat(Quat::from_rotation_x(core::f32::consts::FRAC_PI_2));
-        });
+        self.gizmos.circle(
+            Isometry3d::new(upper_center, circle_rotation),
+            self.radius,
+            self.color,
+        );
+        self.gizmos.circle(
+            Isometry3d::new(lower_center, circle_rotation),
+            self.radius,
+            self.color,
+        );
 
         let connection_lines = upper_points.into_iter().zip(lower_points).skip(1);
         connection_lines.for_each(|(start, end)| {