* signdow 参数添加 是否显示向下箭头标志
* VPSignDown components add.
* Delete the wrongly modified code.
* feat(theme): signdown parameter adds whether to display a downward arrow flag
* feat(theme): signdown marks are changed to be fixed
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Co-authored-by: wb_huyunan <wb_huyunan@kuaishou.com>