A retail company is building a customer-service application that uses a foundation model through the Bedrock Converse API. Before each user message reaches the model, the team must normalize product SKUs (strip whitespace, uppercase them, and expand known abbreviations) and inject the current promotional catalog into the system prompt. The catalog changes several times per day and is fetched from a DynamoDB table. The team wants the cleanest, most maintainable architecture that keeps this logic out of the client and applies it consistently to every request. Which approach best meets these requirements?