Move medipostPrivateMessage.service to separate classes, improve logging

app/api/order/medipost-test-response/route.ts

@@ -54,6 +54,7 @@ export async function POST(request: Request) {
       action: 'send_fake_analysis_results_to_medipost',
       xml: messageXml,
       medusaOrderId,
+      medipostPrivateMessageId: `fake-response-${Date.now()}`,
     });
     await sendPrivateMessageTestResponse({ messageXml });
   } catch (error) {