Design a Kafka topic schema for an e-commerce order processing system.

Topics: orders.order.created (key=orderId), orders.order.updated, orders.order.cancelled, orders.payment.requested (key=orderId), payments.payment.completed, payments.payment.failed, inventory.reservation.requested, inventory.reservation.confirmed. Schema: Avro with Schema Registry for backward/forward compatibility. Partitioning: key=orderId for same-order event ordering. RF=3, minISR=2 for all topics. Retention: 7 days for events, 90 days for audit topics. Separate consumer groups per service. Dead letter topics: orders.order.created-dlt. Use event versioning in Avro schema for evolution.

Expected key concepts: orderId, Avro, Schema Registry, partitioning, RF=3, minISR=2, retention, consumer groups per service, dead letter, event versioning, domain events, e-commerce