Function parse_llm_json 

pub fn parse_llm_json<T: DeserializeOwned>(
    raw: &str,
) -> Result<T, LlmJsonParseError>

Parses LLM JSON output with automatic repair of common errors.

Applies these repairs in order:

1. Strip markdown code fences (json ... )
2. Find the outermost JSON bracket pair
3. Remove trailing commas before } or ]
4. Fix unescaped inner quotes within string values (heuristic)
5. Truncate to the last matching } or ] if there’s trailing garbage

Returns the deserialized value or an error if repair fails.