- Add jsonl_rename_key() function to rename keys in JSONL files with mapping syntax 'old1:new1,old2:new2'
- Implements fast JSON parsing with fastjson and efficient buffered I/O for large files
- Include comprehensive test coverage with 7 test cases for edge cases and valid mappings
- Remove unused tablewriter dependency from go.mod/go.sum and internal/terminal/table.go
- Refactor printResultSummary() to use markdown table printing instead of tablewriter
- Add test data file ffuf-result.jsonl for integration testing
- Fix function list width default calculation in function.go