Code Quality Optimization

1. Remove auto-alignment handling and update docs
   Remove legacy auto-alignment logic and related styles from FormKit component, simplifying the root class binding and always using configured label widths. Update English and Chinese docs to adjust labelWidth example (remove quotes) and remove the 'columns: auto' tip and example blocks. These changes clean up unused conditional behavior and sync documentation with the simplified implementation.
2. Add config.col documentation for grid options
   Introduce the config.col field in both Chinese and English docs to document additional el-col attributes (offset, push, pull, xs, sm, md, lg, xl) supported from Element Plus. Notes that config.span should not be duplicated in col, and includes examples demonstrating offset usage and responsive layout with FormKit code samples.
3. Bind col props to el-col
   Allow passing Element Plus row props via a new rows prop on FormKit and per-column props via conf.col bound to el-col. added v-bind on el-col, and updated types to include ColProps and a col?: Partial in ConfigInterface. This enables customizing el-row/el-col attributes (e.g., alignment, gutter overrides) from form configs.