fix(scan): force-kill stale AE processes before each launch (fresh start)

PrepareFreshAE = taskkill AfterFX/aerender/AfterFXLib/dynamiclinkmanager/QT32
+ 2s settle + clear crash markers, then launch. A hung/zombie AE from a prior
job would otherwise block or corrupt the new run. RunScan now calls it.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

services/node-agent/internal/runner/scan.go

@@ -33,7 +33,7 @@ func WriteScanScript(workDir string) (string, error) {
 // afterfx -r runs the script and the script calls app.quit(); we still poll for the
 // output file because afterfx can return before the file is flushed.
 func RunScan(ctx context.Context, afterfxPath, aepPath, workDir, outPath, mode string) ([]byte, error) {
-	ClearAECrashState() // avoid the "Crash Repair Options" dialog hanging a headless launch
+	PrepareFreshAE() // kill any stale AE + clear crash/Safe-Mode markers → guaranteed fresh launch
 	scriptPath, err := WriteScanScript(workDir)
 	if err != nil {
 		return nil, fmt.Errorf("write scan script: %w", err)