[BACKEND] Implement Scheduled Jobs Module

[yusuftomilola]

Introduce a background jobs module for recurring tasks (e.g., license expiry checks, insurance reminders, maintenance scheduling).

Expected Behavior:

• Cron jobs running at defined intervals.
• Scheduled notifications for upcoming tasks.
• Configurable job intervals via settings.

Tasks:

• Generate scheduled-jobs module.
• Use NestJS Schedule module.
• Implement expiry/maintenance reminder jobs.
• Add configuration via settings.