Advanced AI Prompt for Content Versioning and Audit Trails

Act as a Database Audit and Compliance Engineer. Design a bulletproof system for managing content versioning and immutable historical audit trails entirely within DynamoDB. Given the highly nested [DATA_STRUCTURE], implement a 'Version Stacking' schema where every mutation is permanently tracked with a precise timestamp and executing UserID. Detail the PK/SK strategy required to fetch the 'v0' (latest) item with O(1) efficiency, while preserving the ability to query the entire historical ledger to satisfy strict [AUDIT_REQUIREMENTS]. Discuss the architecture for utilizing DynamoDB Streams combined with Kinesis Firehose to automatically offload and archive historical versions to immutable S3 buckets after the [VERSION_RETENTION] period expires.