Implement temp file cleanup for chartify and helmfile temp files

Co-authored-by: yxxhero <11087727+yxxhero@users.noreply.github.com>

pkg/config/global.go

@@ -70,6 +70,8 @@ type GlobalOptions struct {
 	Args string
 	// LogOutput is the writer to use for writing logs.
 	LogOutput io.Writer
+	// CleanupTempFiles enables cleanup of old temporary files on startup.
+	CleanupTempFiles bool
 }
 
 // Logger returns the logger to use.