Tags: codingapi/form-engine

feat: 支持字段级只读属性 readOnly

- FormField 类型新增 readOnly 属性
- FormItemFactory.render 字段级 readOnly 优先于预览模式只读
- 版本号升级 0.0.19

Co-Authored-By: Claude <noreply@anthropic.com>

add option

add className

update refresh

update readme

update version

update version

update version

add README.md