fix(queue): renew live claim leases

[Joncallim]

Source Issue

Issue: #179

Summary

• renew active queue claim timestamps with Redis TIME while keeping the ownership nonce stable
• make acknowledgement, release, retry, and dead-letter transitions authorize the stable nonce after renewal
• start a bounded, non-overlapping heartbeat before task lookup or business work and drain it before terminal queue transitions
• prove renewal, response loss, ownership loss, recovery, shutdown, and timer cleanup across task, approval, and answers queues

Stack

• Base branch: codex/pr198-producer-5a2-core-diagnostics
• Exact base SHA: 7facc2b25503bfeecf2ea19ab8a00dc9bc8fb1a5
• This is a draft stacked child for PRODUCER-5A2-R3B-LIVE-CLAIM-RENEWAL.

Validation

• npx vitest run __tests__/core-diagnostic-output-closure.test.ts — 23/23
• dedicated Redis proof — 3/3 on Redis 8.8 using disposable database 13
• npm test -- --reporter=dot — 1,691 passed, 30 skipped integration tests
• npx eslint worker/queue.ts worker/runtime.ts __tests__/core-diagnostic-output-closure.test.ts __tests__/queue-occurrence-recovery.redis.test.ts
• npx tsc --noEmit
• npm run build
• git diff --check

Mutation evidence

• restoring full timestamp-plus-nonce equality made the source contract fail because all four terminal transitions must use stable nonce ownership
• disabling periodic renewal made the runtime heartbeat test fail after only the initial renewal

Scope

Only the two queue/runtime modules and their two existing focused proof files change. No schema, documentation, workflow, UI, or new Redis key family is included.