Max Vray: Add check on SplitAlpha to ensure the options align with expectedFiles.

[moonyuet]

Changelog Description

This PR is to add check on splitapha to ensure the options align with expectedFiles so that it won't error out when the alpha option is disabled.

Additional review information

n/a

Testing notes:

1. Create Render Instance with Vray as main renderer
2. Publish Render with enabling/disabling Save Alpha

3. Both should be working

[LiborBatek]

currently as I have tested with 3dsmax 2026 and latest Vray 7 its not working with Vray frame buffer and VRay Raw Output and need to be switched to classic native 3dsmax outputs/render elements so couldnt be tested right now (as it fails to render on DL constantly) once switched for the testing setup in this PR.

I will postpone the testing for later once we are having some solution for these...

[LiborBatek]

I was able to publish/render the sequence (save Alpha disabled option) but my DL publish job fails...

Im enclosing reports and logs plus metadata json for your inspection,..
DL-Publish-Job_2026-01-05_15-31-27_695bcb3fbb6057696fca0167.txt
MAX-publish-report-260105-15-17.json.txt
maxrenderMain_metadata.json.txt

[moonyuet]

@LiborBatek the bug has been fixed in c556da6 and I also find out that we need to add some validation check on vray aov in regard to some new commits, just FYI.