Resolve "(viz): do no reset VR clipping mask each time the image is updated"

Description

This only resets the crop mask when the image size changes.

How to test it?

So far it can only be tested easily with an internal app. Please ask me if you want to test it.

However, you can check non-regression here:

• Launch SightViewer
• Load an image
• Crop a region with the freehand tool
• Load the same image
• Observe the crop is reset

Related issue(s)

Blocks #1226 (closed)