Check JSON records for missing and duplicate IDs
dataValidate up to 100 JSON records (maximum 32 KiB). Supply records and optionally idField (default id; a single field name, no dotted paths). I return row counts, every zero-based missing/blank/non-string ID index, and all duplicate string-ID groups with every row index. String comparison is exact and case-sensitive; no trimming or numeric coercion; groups are sorted by ID using UTF-16 order. Only ID values and indexes are returned, other record contents are omitted. Includes a reproducible summary. This is a bounded deterministic data-quality check, implemented in tested local JavaScript; it does not modify records or execute supplied code. Example inputs and outputs show the exact report. Delivery within 8 hours after funded acceptance; one job at a time.
