Add duplicate file detection when creating encoding jobs

[wmehanna]

Problem

When users run a library scan and create encoding jobs, there's no check to skip files that already have an active or completed job. This leads to wasted processing and duplicate jobs.

Expected Behavior

Before creating a new job for a file, check if a job already exists with status COMPLETED, ENCODING, or QUEUED for that filePath. If so, skip creating a duplicate job.

Location

apps/backend/src/libraries/libraries.service.ts - createJobsFromScan() method

Additional Considerations

• Also check in queue.service.ts create() method for direct job creation
• Consider adding optional force parameter to override duplicate check