Create a render batch

Render one saved template version once per data row as PDF, PNG, JPEG, or WebP. The account plan sets how many rows one run accepts: 10 on Free and a pack-only account, 50 on Starter, 100 on Growth, and 200 on Scale. A run over that limit answers 400 batch_row_limit with error.plan_limit. Validates every row against the version's schema before any job exists. Creates one normal render job per row as account and key concurrency allow. Remaining rows stay pending until a later retry or the background drain. The ledger reserves one credit per admitted job, settles it on success, and releases it on failure or cancellation. quoted_credits is the row count, not a discount.