Returns the cost of your AI calls per product, in USD, split into time buckets (hourly, daily or monthly, depending on the length of the date range). Only calls that name a product are counted. Use products to keep only some products, and costSource to count only metered or provider-billed cost. For one figure per group over the whole period, a far smaller answer over a long date range, use get_cost_by_product_aggregated, which does not take products.