- Rename Append to Merge on Cookies, Headers, and Params types and simplify Parse to use direct append
- Replace strings_Join(sep, ...values) with slice_Join(slice, sep) for consistency with slice-based template functions
- Auto-enable quiet mode when stdout is not a terminal
- Remove ErrCLINoArgs check to allow running sarin without arguments
- Add -it flag to Docker examples in docs
Replace ad-hoc fmt.Errorf/errors.New calls with typed error structs across config, sarin, and script packages to enable type-based error handling. Add script-specific error handlers in CLI entry point. Fix variable shadowing bug in Worker for scriptTransformer. Bump Go to 1.25.7 and golangci-lint to v2.8.0.