Convert XML to clean JSON. POST raw XML (XML or text/plain Content-Type) or a JSON envelope {xml, alwaysArray}. Attributes land under "@_" keys, mixed-content text under "#text", repeated siblings become arrays, and alwaysArray forces arrays for listed tags even on a single occurrence. Numeric character references decode. DTD entities and DOCTYPE internal subsets rejected (anti-XXE / billion-laughs). Max 5 MB.