- DnsServers now uses Events\HasAgentCommands (agent identifier lives in its
  own agent_uuid column, not the model's uuid).
- PowerDnsProviderService dispatches via $server->sendAgentCommand() instead
  of calling AgentCommandsService directly.
- Replace the never-deployed ListenPdnsAgentEvents Artisan command with
  HandlePdnsAgentEventJob, a queued Job dispatched by the generic
  events:nats-listen command - this is the first time zone/record
  provisioning -> active/failed reconciliation actually runs in production.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>