[TASK] Add validation and troubleshooting steps to documentation

[eternaltyro]

Add steps to verify that the app is working well.

• To verify redis connectivity, access /snapshot endpoint with default value , you should get a task id in successful response
• To verify that workers are active, grab that task id from the previous step and pass it to /tasks/status/{task_id}/
  • If you get success in response with download URL, that means workers are functional
• To test access to AWS S3 bucket - Grab that download URL from previous response and open it in a browser window. If you can download the file that means bucket is accessible

[github-actions]

Warning : This issue is stale because it has been open for 30 days with no activity. It will be closed if no activity found within 15 days.