Tests STOMP over WebSocket (Spring, ActiveMQ, RabbitMQ Web STOMP) and AMQP 0-9-1 (RabbitMQ Java client) - frame connect/subscribe/send/ack sequences, ack modes (auto/client/client-individual), exchange and queue declarations, binding routing, Testcontainers RabbitMQ broker, and delivery assertion. Use when validating enterprise Spring or RabbitMQ messaging stacks before deploy.