Eliminate (or at least significantly reduce) build warnings in VTK 9 release builds
Context: In my custom build of the unmodified 9.2.2 sources (only activating opengl, stl files handling extra modules) more than a thousand warnings could be counted on my recent 9.2.2 source code release builds, using VS2022. I also built ITK and could not observe such a significant amount of warnings for ITK.
Motivation: Once I get agreement about potential approaches to resolve these warnings, I'd like to participate and fix a significant part of these warnings and propose merge requests for them and maybe more interesting material later too.
For my initial contribution proposal please read: https://discourse.vtk.org/t/cleanup-warnings-in-current-vtk-9-plans/9586
I can make a quick proof of concept and fix say a dozen only of warnings if needed, please let me know, would be really glad to start helping and contributing on vtk.
-Fab