Add new sample scenes

[shaynie]

Overview

Changes

• Fixes: Polish new MRTK3 samples #11672 .

Verification

This optional section is a place where you can detail the specific type of verification
you want from reviewers. For example, if you want reviewers to checkout the PR locally
and validate the functionality of specific scenarios, provide instructions
on the specific scenarios and what you want verified.

If there are specific areas of concern or question feel free to highlight them here so
that reviewers can watch out for those issues.

As a reviewer, it is possible to check out this change locally by using the following
commands (substituting {PR_ID} with the ID of this pull request):

git fetch origin pull/{PR_ID}/head:name_of_local_branch

git checkout name_of_local_branch

[AMollis]

Looks good... I agree with Marlena's comments.

For the samples, it's probably ok to leave some summary blocks out...but add the following to the top and bottom of the sample files if you do:

// Disable "missing XML comment" warning for sample. While nice to have, this documentation is not required for samples. #pragma warning disable CS1591

#pragma warning restore CS1591

This will prevent warnings for missing XML documentation during the build process.

[AMollis]

I sign-off ... assuming @marlenaklein-msft does as well