Repair malformed JSON text into valid parsed JSON: markdown code fences, single quotes, smart quotes, unquoted keys, trailing commas, comments, Python literals (True/None), raw newlines in strings, and truncated output (auto-closes strings, arrays and objects). Returns the parsed value plus a log of every repair applied. Built for LLM output that almost parses. POST a JSON body like: {"text":"```json\n{name: 'Ada', age: 36, tags: ['x',], active: True"}