chore: import upstream snapshot with attribution

scripts/check_powershell_syntax.ps1

@@ -0,0 +1,44 @@
+param(
+    [string[]]$Paths = @("scripts")
+)
+
+$ErrorActionPreference = 'Stop'
+Set-StrictMode -Version Latest
+
+$scriptFiles = @()
+foreach ($path in $Paths) {
+    if (-not (Test-Path -LiteralPath $path)) {
+        continue
+    }
+
+    $scriptFiles += Get-ChildItem -LiteralPath $path -Recurse -File -Filter '*.ps1'
+}
+
+if (-not $scriptFiles -or $scriptFiles.Count -eq 0) {
+    Write-Host 'No PowerShell scripts found.' -ForegroundColor Yellow
+    exit 0
+}
+
+$hadErrors = $false
+
+foreach ($file in $scriptFiles | Sort-Object FullName -Unique) {
+    $tokens = $null
+    $errors = $null
+    [System.Management.Automation.Language.Parser]::ParseFile($file.FullName, [ref]$tokens, [ref]$errors) | Out-Null
+
+    if ($errors -and $errors.Count -gt 0) {
+        $hadErrors = $true
+        Write-Host "Parse errors in $($file.FullName):" -ForegroundColor Red
+        foreach ($error in $errors) {
+            $line = $error.Extent.StartLineNumber
+            $column = $error.Extent.StartColumnNumber
+            Write-Host "  Line ${line}, Col ${column}: $($error.Message)" -ForegroundColor Red
+        }
+    } else {
+        Write-Host "OK: $($file.FullName)" -ForegroundColor Green
+    }
+}
+
+if ($hadErrors) {
+    exit 1
+}