HarmonyOS RichEditor使用问题

参考demo，可以使用this.controller.addTextSpan(""\n"")来进行换行：

@Entry
@Component
struct RichEditorDemo2 {
  @State message: string = 'Hello World';
  controller: RichEditorController = new RichEditorController();
  options: RichEditorOptions = { controller: this.controller };
  build() {
    Column() {
      RichEditor(this.options)
        .onReady(() => {
          this.controller.addTextSpan(""012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789\n"",
          {
            style:
            {
              fontColor: Color.Orange,
              fontSize: 30
            }
          })
          this.controller.addImageSpan($r(""app.media.app_icon""),
          {
            imageStyle:
              {
                size: [""200px"", ""200px""],
                verticalAlign: ImageSpanAlignment.BOTTOM,
                layoutStyle: {
                borderRadius: { topLeft: '10px', topRight: '20px', bottomLeft: '30px', bottomRight: '40px' },
                margin: { left: '10px', top: '20px', right: '30px', bottom: '40px' }
              }
              },
            })
          this.controller.addTextSpan(""\n"")
          this.controller.addTextSpan(""0123456789"",
          {
            style:
            {
              fontColor: Color.Orange,
              fontSize: 30
            }
          })
        })
    }
    .height('100%')
  }
}