Resolve "fix(viz): 32bits images are not displayed correctly"

Description

This restores partially the behavior prior to 1353d895 that converts 32 bits integer images into 16 bits images when uploading them on the GPU. This fixes a regression that prevents from reading all 32 bits integer DICOMs.

Closes #964 (closed)

How to test it?

• Load the image mentioned in #964 (closed)