Implement Job Manager

[Lucas0T]

Job Handling Concept

1. Global Job Manager Service

   Service in the application (one instance)
   Manages a job registry (in-memory + persisted directly in the filesystem where the bundles are located)
   Responsible for:
   Creating jobs (from incoming FHIR Task requests)
   Tracking job lifecycle
   Handling scheduling & queuing
   Restarting jobs from checkpoints
   Cleaning up old/finished jobs
   Provides API endpoints via FHIR Task to list, delete/cancel, and query jobs

2. Job Class

   Each job is represented by a Job object that are persisted
   Contains:
   jobId : UUID (time based)
   status : PENDING | RUNNING | PAUSED | FAILED | COMPLETED
   progress : {lastBatchIndex, lastPatientRef, checkoint reference}
   issues : List of OperationOutcome.issue (errors/warnings)
   startedAt, updatedAt, finishedAt
   The Job entity can be parsed or serialized to lightweight JSON (fits in JSON DB or SQL row)