Windows ML: Add folder partitioning for native samples and fix some build errors

[adrastogi]

Description

A longstanding problem with the native Windows ML samples is that they share a common output directory, which results in their outputs overwriting each other (especially when building via the build.cmd script). This change adds a fix to separate those outputs so that each sample's binaries land in a different folder. This will better enable scenarios like pipeline automation.

I also noticed that there were some packages missing from the shine-oss feed which I worked with the WASDK team offline to add. And then there were a couple build errors caused by duplicate packaging and a missed macro in the GenAI project, so I tried to resolve those as well.

Target Release

2.0

Checklist

Note that /azp run currently isn't working for this repo.

• Samples build and run using the Visual Studio versions listed in the Windows development docs.
• Samples build and run on all supported platforms (x64, x86, ARM64) and configurations (Debug, Release).
• Samples set the minimum supported OS version to Windows 10 version 1809.
• Samples build clean with no warnings or errors.
• [For new samples]: Samples have completed the sample guidelines checklist and follow standardization/naming guidelines.
• Microsoft employees only: you can validate your changes by following the instructions here: https://www.osgwiki.com/wiki/WindowsAppSDK-Samples

[adrastogi]

Holding off on merging this one for now; there's some deviation between this branch and release/experimental which needs to be reconciled as it relates to building the samples.

[Edit: I think it should be ok to merge these changes after all, so I'll proceed with that.]