WorkerConfigLoader

Loads a run queue worker's settings (Stage 5 W2, design 4.56) from llm4s.agent.worker: concurrency, pollInterval, unrunnableAfter, the drain block (grace, exitTimeout), the sweep block (enabled, every, batchSize, an optional tombstoneAge and an optional retention block of maxAge, maxCheckpoints and maxEvents) and an optional label, with the defaults of llm4s-agent's reference.conf. The queue's own settings

• the lease, maxAttempts, the ticket lifetime - are RunQueueConfigLoader's; the store is CheckpointerConfigLoader's.