Job Manager for Task Scheduling

Description

A JobManager will be implemented for each library to schedule, execute, and monitor background tasks. It will be built on top of a generic TaskSystem for concurrency management.

Implementation Notes

• The JobManager will be defined in src/infrastructure/jobs/manager.rs.
• It maintains its own private database (jobs.db) for storing job state, history, and checkpoints.
• It is responsible for resuming interrupted jobs on startup.
• It provides APIs to dispatch, pause, and resume jobs.

Acceptance Criteria

• Each library has its own JobManager instance.
• The manager can dispatch a new job and return a JobHandle.
• The manager can list jobs by status by querying both memory and its database.
• Interrupted jobs (e.g., from a crash) are correctly paused and can be resumed on next startup.