test(M00): record final paired evidence

tools/run_render_baseline.ps1

@@ -40,6 +40,15 @@ function Invoke-GodotStep {
     }
 }
 
+function Invoke-GodotComparisonStep {
+    param([string]$Name, [string[]]$Arguments)
+    Write-Host "[$Name] $GodotPath $($Arguments -join ' ')"
+    $process = Start-Process -FilePath $GodotPath -ArgumentList $Arguments -NoNewWindow -Wait -PassThru
+    if ($process.ExitCode -notin @(0, 1)) {
+        throw "$Name failed with exit code $($process.ExitCode)"
+    }
+}
+
 Push-Location $repoRoot
 try {
     Invoke-GodotStep "project-load" @("--headless", "--path", ".", "--quit")
@@ -80,7 +89,7 @@ try {
 			"--viewport-height", $VisualComparisonHeight.ToString()
 		)
 		Invoke-GodotStep "visual-capture" $visualCaptureArgs
-        Invoke-GodotStep "visual-comparison" @(
+        Invoke-GodotComparisonStep "visual-comparison" @(
             "--headless", "--path", ".",
             "--script", "res://src/tools/compare_render_checkpoints.gd",
             "--",