feat: use horizon queues and cronjob scheduler

Background

Since queues on IMEX are using Redis, and we have horizon installed for monitoring, we should be using horizon to run the queues.

Action Plan / Actions Taken

• Removed previous queue runner mechanism.
• Use horizon directly to start queue runners
• Updated worker monitoring (readiness/liveness) to use horizon:status
• Increased resource limits and balanced production maxProcesses configuration for memory use

Added tests?

• Yes, of course
• No, and here's why: no code changes, just config & deployment values
• I need help writing tests

Requirements

• None

How to test

• Code review.
• Review the new/updated tests carefully: are they correct, sufficient, and passing?
• Ensure auto-deploy-values file is correctly formatted.
• Test using deployment from: https://git.customd.com/imex/api/-/merge_requests/134
• Try and break it!