feat(文档): 添加RImg组件并配置资源路径别名

删除未使用的Custom.vue组件，新增RImg组件用于处理资源图片路径
在vite配置中添加资源路径别名，简化图片引用方式
更新client.ts注册RImg组件

docs/.vuepress/client.ts

@@ -1,22 +1,8 @@
 import { defineClientConfig } from 'vuepress/client'
-// import RepoCard from 'vuepress-theme-plume/features/RepoCard.vue'
-// import NpmBadge from 'vuepress-theme-plume/features/NpmBadge.vue'
-// import NpmBadgeGroup from 'vuepress-theme-plume/features/NpmBadgeGroup.vue'
-// import Swiper from 'vuepress-theme-plume/features/Swiper.vue'
-
-// import CustomComponent from './theme/components/Custom.vue'
-
-// import './theme/styles/custom.css'
+import RImg from './theme/components/RImg.vue'
 
 export default defineClientConfig({
   enhance({ app }) {
-    // built-in components
-    // app.component('RepoCard', RepoCard)
-    // app.component('NpmBadge', NpmBadge)
-    // app.component('NpmBadgeGroup', NpmBadgeGroup)
-    // app.component('Swiper', Swiper) // you should install `swiper`
-
-    // your custom components
-    // app.component('CustomComponent', CustomComponent)
+    app.component('RImg', RImg)
   },
 })