[Backend][Tech-debt] Background job handlers are no-op stubs that mark work complete without doing it

[Penielka]

Overview

In backend/src/index.ts the job queue registers handlers for email, notification, report_generation, data_export, credential_minting, analytics_aggregation, content_processing and general — every one of them only logs the job and sets job.progress = 100. Jobs enqueued by real features (e.g. credential minting, data export) are therefore reported as successfully completed while doing nothing.

Evidence

• backend/src/index.ts — jobQueue.registerHandler(...) block

Acceptance Criteria

• Implement or remove each handler; never mark a job complete without performing its work
• Return a terminal failure state for unsupported job types
• Add tests asserting handlers actually process or explicitly fail

Files to Modify

• backend/src/index.ts

Priority: Medium