Added V2 Invoice Reports Guide
Invoice Reports provide a daily summary of the invoices associated with an organization. The V1 Invoice Summary provided a snapshot of in-progress data, whereas the V2 Invoice Summary ensures that customers receive complete and finalized data sets, addressing scenarios where invoices span multiple days. The V1 Invoice Summary will be deprecated after 2026-10-31. Organizations can request historical backfill data for the V2 Invoice Summary by providing the org_id and backfill_start_date in an Admin Support ticket.
