[BE-57] Add integration tests for the queue processing pipeline

[mftee]

Overview

The BullMQ queue pipeline (analyze → anchor) has no test coverage. A bug in the processor silently corrupts document state with no failing test to catch it.

Acceptance Criteria

• Use a real Redis instance (test container or local) — do not mock BullMQ
• Test the full analyze job: document status transitions PENDING → ANALYZING → VERIFIED/FLAGGED
• Test the full anchor job: VerificationRecord created with correct status
• Test job failure: document status set to REJECTED after all retries exhausted
• Test job deduplication: second anchor job for the same document is not enqueued