Create items on a list, many in one call

Create items on one list, many in one call (1 to 100): a to-do or a dictated list of them on the Tasks list, a note on the Notes list, rows of a reading list or a CRM. Each entry carries a title, a body as Markdown, and values for the list's own properties as {propertyId, value} pairs (ids or names from list_lists; a select value may be its label or option id, a multiSelect value an array of them; an unknown label becomes a new option). On a list that keeps a status and a due date an entry may set taskStatus, dueAt (a day, or a local time when one was stated, which also arms a reminder at that moment) and reminderAt (a reminder on a day, at the person's default reminder hour). The items are stored as written and indexed for search; no AI pass runs unless enrich is true, which on a tasks list derives the title and due date from the words. An entry's externalId (the caller's own id) makes re-sending safe: the same externalId returns the item already made, under existing. With matchOn, an entry whose named values match an existing item fills that item's empty values, body and images and overwrites nothing (changing a filled value is update_items' job); without it every entry is inserted. Images come as imageUrls (a Roma storage path from create_image_upload, or a public https image URL the server downloads); failures come back in imageFailures. One bad entry never fails the batch; it is reported under failed with its reason.