[Bug report] Deprecation Warning: Sass @import rules are deprecated in VuePress theme

[yhl-186]

Description

在使用 VuePress 时，我收到了以下关于 Sass @import 的弃用警告：
"sass": "^1.80.3",
"vue": "^3.4.0",
"vuepress": "^2.0.0-rc.7"

  ╷
2 │ @import '@vuepress/plugin-palette/palette';
  │         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  ╵
    node_modules\.pnpm\@vuepress+theme-default@2.0.0-rc.55_markdown-it@14.1.0_sass@1.80.3_vuepress@2.0.0-rc.18_@vuep_w6rbselmw7b23k3zh7mmjp3yoa\node_modules\@vuepress\theme-default\lib\client\styles\_variables.scss 2:9        @import
    node_modules\.pnpm\@vuepress+theme-default@2.0.0-rc.55_markdown-it@14.1.0_sass@1.80.3_vuepress@2.0.0-rc.18_@vuep_w6rbselmw7b23k3zh7mmjp3yoa\node_modules\@vuepress\theme-default\lib\client\styles\_mixins.scss 1:9           @use
    node_modules\.pnpm\@vuepress+theme-default@2.0.0-rc.55_markdown-it@14.1.0_sass@1.80.3_vuepress@2.0.0-rc.18_@vuep_w6rbselmw7b23k3zh7mmjp3yoa\node_modules\@vuepress\theme-default\lib\client\components\VPSidebarItem.vue 2:1  root stylesheet

Warning: 1 repetitive deprecation warnings omitted.
Run in verbose mode to see all warnings.
`
Deprecation Warning: Sass @import rules are deprecated and will be removed in Dart Sass 3.0.0.```

### Reproduction

pnpm create vuepress vuepress-starter

### Used Package Manager

pnpm

### System Info

```shell
More info and automated migrator: https://sass-lang.com/d/import       

  ╷
2 │ @import '@vuepress/plugin-palette/palette';
  │         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  ╵
    node_modules\.pnpm\@vuepress+theme-default@2.0.0-rc.55_markdown-it@14.1.0_sass@1.80.3_vuepress@2.0.0-rc.18_@vuep_w6rbselmw7b23k3zh7mmjp3yoa\node_modules\@vuepress\theme-default\lib\client\styles\_variables.scss 2:9        @import
    node_modules\.pnpm\@vuepress+theme-default@2.0.0-rc.55_markdown-it@14.1.0_sass@1.80.3_vuepress@2.0.0-rc.18_@vuep_w6rbselmw7b23k3zh7mmjp3yoa\node_modules\@vuepress\theme-default\lib\client\styles\_mixins.scss 1:9           @use
    node_modules\.pnpm\@vuepress+theme-default@2.0.0-rc.55_markdown-it@14.1.0_sass@1.80.3_vuepress@2.0.0-rc.18_@vuep_w6rbselmw7b23k3zh7mmjp3yoa\node_modules\@vuepress\theme-default\lib\client\components\VPSidebarItem.vue 2:1  root stylesheet

Warning: 1 repetitive deprecation warnings omitted.
Run in verbose mode to see all warnings.

Deprecation Warning: Sass @import rules are deprecated and will be removed in Dart Sass 3.0.0.

[phnglh]

I have this problem too

[ntnyq]

The warnings can be suppressed by setting in config.ts:

import { viteBundler } from '@vuepress/bundler-vite'
import { defineUserConfig } from 'vuepress'

export default defineUserConfig({
  bundler: viteBundler({
    viteOptions: {
      css: {
        preprocessorOptions: {
          scss: {
            silenceDeprecations: ['import'],
          },
        },
      },
    },
  }),
})