Add failed queue retries for jobcreator messages

[Dagonite]

Closes #423.

Summary

• Add FAILURE_QUEUE_NAME support for jobcreator, defaulting to failed-scheduled-jobs.
• Route failed ingress messages to the failed queue before acking the original message.
• Retry messages from the failed queue and republish them on repeated failure.
• Make JSON decode errors, job processing failures, and unknown job_type values propagate into retry handling.
• Add tests for failed queue declaration, publish-before-ack behavior, retry handling, and main wiring.

Testing

• pytest job_creator/test -q

GitOps change

fiaisis/gitops#296