rishabht877/TransactIQ ? reverse-engineered prompt

Build me a distributed payment processing app that can accept payments through a REST API, make sure the same request never gets charged twice, and process everything asynchronously through Kafka. I want a small gateway service, a payment processor, and a fraud triage service that uses simple rules first and then an LLM for a final approve, block, or escalate decision with a clear human readable reason. Please include MySQL for payment state and outbox style event publishing, Redis for idempotency, and proper retry and dead letter handling.

I also want a simple React dashboard where I can submit a payment and see the current status, fraud decision, risk score, and explanation update over time. Add health checks, metrics, Prometheus and Grafana, plus Docker Compose so I can run everything locally. If it helps, look up current docs online for the best way to wire the latest Spring Boot, Kafka, and LangChain4j pieces together.