Initial DOS VM tooling setup

.qemu/screenshot.ps1

@@ -0,0 +1,26 @@
+param(
+    [string]$Name = 'qemu-screen',
+    [switch]$KeepPpm
+)
+
+$ErrorActionPreference = 'Stop'
+$ffmpeg = Get-Command ffmpeg.exe -ErrorAction Stop
+
+$target = if ([IO.Path]::IsPathRooted($Name)) { $Name } else { Join-Path $PSScriptRoot $Name }
+$extension = [IO.Path]::GetExtension($target)
+if ($extension -in @('.png', '.ppm')) {
+    $target = [IO.Path]::Combine([IO.Path]::GetDirectoryName($target), [IO.Path]::GetFileNameWithoutExtension($target))
+}
+$directory = [IO.Path]::GetDirectoryName($target)
+if ($directory) { New-Item -ItemType Directory -Force -Path $directory | Out-Null }
+
+$ppm = "$target.ppm"
+$png = "$target.png"
+$qemuPath = $ppm.Replace('\', '/')
+
+& (Join-Path $PSScriptRoot 'monitor.ps1') "screendump $qemuPath" | Out-Null
+if (-not (Test-Path -LiteralPath $ppm)) { throw 'QEMU did not create the requested screenshot.' }
+& $ffmpeg.Source -y -loglevel error -i $ppm $png
+if ($LASTEXITCODE -ne 0) { throw "ffmpeg conversion failed with exit code $LASTEXITCODE." }
+if (-not $KeepPpm) { Remove-Item -LiteralPath $ppm -Force }
+Get-Item -LiteralPath $png