Enable Windows CI w/ TPLs

[kennyweiss]

Summary

• This PR reworks our CI on Windows to use TPL builds from the "manual Windows TPL" CI, similar to our docker-based workflow.
• We can now generate a TPL set via the "manual Windows TPL" github actions, which will cache the vcpkg builds
• In our ci-tests.yaml github action, we pull in the cached TPLs and use then in our testing
  • For this initial setup, we're only testing the x64-windows Debug config in our on-commit CI-tests
  • We can easily add the other Windows configs ({x64, x86}, {Debug, Release}) as desired
• Resolves Add github action for manual Windows TPL builds #546

[kennyweiss]

Reverted to draft...
It seemed like this was working, but the ci-test plan is not finding the cache from the "manual Windows build" plan.

Might be a mismatch in my expectations for caches. From the docs:

Workflow runs cannot restore caches created for child branches or sibling branches.