rust-codebase dev proxy

HTTP paths:
  /minio/           MinIO S3 API
  /minio-console/   MinIO web console
  /webhook/         webhook-service
  /chat/            chat-service
  /ai/              ai-service
  /rtc/             rtc-service
  /relay-ws/        relay WebSocket

DB / Redis / NATS access: not exposed. Use dev-only API endpoints (TBD).