All shims defaulted to F:\CI\python\venv\Scripts\python.exe when
CI_VENV_PYTHON was not set. On Linux host this caused instant failure.
Now uses $IsWindows (PS 6+ automatic var; absent on PS 5.1 = Windows)
to select /opt/ci/venv/bin/python on Linux. Windows paths unchanged.
Affects: Invoke-CIJob, Get-BuildArtifacts, Cleanup-OrphanedBuildVMs,
New-BuildVM, Remove-BuildVM, Wait-VMReady, Get-CIJobSummary,
Invoke-RemoteBuild, Watch-DiskSpace, Watch-RunnerHealth,
Set-CIGuestCredential, Test-CIGuestWinRM.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
The blind -X -> --x shims forwarded PowerShell common parameters
(-ErrorAction, -Verbose, ...) to the Python CLI, e.g.
Measure-CIBenchmark.ps1 -> Remove-BuildVM.ps1 -ErrorAction
SilentlyContinue produced `ci_orchestrator vm remove --error-action`
-> "No such option" -> destroy failed (orphan VM left). Skip
common switches and consume value-taking ones. Applied to all 7
blind-loop shims; param-style shims (New-BuildVM, Invoke-RemoteBuild,
Get-BuildArtifacts) are not affected. PSSA clean.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>