fix(viz): cropbox reset freezes SightViewer

Description

We avoid a deadlock in SVolumeRender::updateClippingBox() by unlocking the clipping matrix data before calling the interaction callback.

Closes #694 (closed)
Closes #698 (closed)

How to test it?

• Run SightViewer
• Load an image
• Click on the reset button

Data

You need a medical image.