#121 Fix: Reduce claim_timeout from 30s to 10s for faster crash recovery

IMMEDIATE FIX for disruption resilience. Location: engine/orchestrator.py:727, engine/cli/worker.py:374 Changes needed: 1. Add --claim-timeout CLI argument to worker.py (default: 10) 2. Pass claim_timeout to orchestrator.claim_and_execute_tasks() 3. Update systemd service files to use 10s timeout Trade-off: Long tasks need more frequent heartbeats with shorter claim timeout. Parent: #116