wakeRouter now retries failed agent-wake dispatches instead of dropping them

The background wake dispatcher that delivers queued commands to agents no longer drops a delivery on the first failure. It now classifies each outcome as delivered, dropped, or retry: non-terminal failures (not an abort/stop error, and under a retry cap) are rescheduled with jittered exponential backoff using a new per-agent timer map. Commands are only dropped, with a new resume_failed reason, once an error isn't retryable or the retry-count cap is reached.