windows.yml: parse job (every .ps1 through the Windows PowerShell 5.1 parser with a negative fixture, PSScriptAnalyzer
as warnings, parenthesis check of every .bat/.cmd with a negative fixture), build job (engine on the MSVC target,
window host through BUILD-APP.bat as it is, payload through make-payload.sh in Git Bash, installer through
build-installer.ps1, smoke run of both exes, launcher DRY_RUN, three artifacts for 90 days).
push-inputs.sh publishes payload-inputs.zip (node, miner, workers, NVRTC DLLs) to the downloads host from the Mac;
fetch-ci-artifacts.sh pulls the green run's installer and payload back into the downloads folder.
Host: --version and --help, version.h shared with host.rc. Launcher: DRY_RUN=1 prints the plan and starts nothing.
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
