fix(cpn): bundle MSVC++ redist with win64 installer

[elecpower]

Fixes #6519

Summary of changes:

• install vs_redist.x64.exe sourced from compiler environment

[pfeerick]

Both local build and Github build are pulling in the x86 redist, and thus nether install detection/verification (since x86 uses a different registry key) nor Companion will work on a clean system (testing using Windows Sandbox, as that is clean slate every run). Killing x86 in cmake\FindMSVCRedist.cmake seems to work locally... leave it at that, or do you think there is a better way to do this?

[elecpower]

Cajoling seems to be the most reliable though less flexible approach. Build priority is obviously GitHub and 'default' local vc++ install. Suppose we could always add an environment variable to force cmake find to also look in non-default location.

[pfeerick]

So you're happy to leave this as it is until (if? or is that being too optimistic? 😆 ) it blows up on us in the future? Yes, I did say "us". ;)

[elecpower]

Almost guaranteed to blow up. We are dealing with Windows. But let's go with what we have.