- Handle nested arrays in JSON (src/dsq-formats/src/reader/json_utils.rs:103)
- Handle nested objects in JSON (src/dsq-formats/src/reader/json_utils.rs:104)
- Fix date/time format options for CSV (src/dsq-io/src/formats/csv.rs:65)
- Implement proper lazy CSV reading using LazyCsvReader/scan_csv instead of eager read + .lazy() conversion (src/dsq-formats/src/reader/file_reader.rs:117-127)
- UDF implementations.