GenServer for managing orphaned/disowned jobs.

When a job is disowned via the disown builtin, it is detached from the session and monitored by this supervisor. This ensures the job continues running even after the session terminates.

Unlike session-supervised jobs, orphaned jobs:

• Do not notify any session on completion
• Continue running until they exit naturally or are killed
• Are not affected by session termination
• Are monitored by this supervisor for tracking purposes