A customer expects data volume and user concurrency to grow over the next 12 months and wants a lightweight planning tool. Write a program that takes monthly forecasts for data ingest, storage growth, query concurrency, and target p95 latency, then estimates the compute capacity required for both batch ingestion and interactive analytics. Your solution should flag months where projected demand exceeds configured capacity, recommend when to scale up or scale out, and estimate monthly infrastructure cost under at least two deployment options. Keep the model simple but explicit, and document the assumptions your code makes so they can be challenged in a customer conversation.