feat: 定期检查文档更新并弹出提醒

- 扩展基础主题代码做抽取

docs/.vitepress/theme/setupMediumZoom.ts

@@ -0,0 +1,16 @@
+import { nextTick, watch } from 'vue'
+import { useRoute } from 'vitepress'
+import mediumZoom from 'medium-zoom'
+
+export function setupMediumZoom() {
+  if (import.meta.env.SSR) return
+
+  const route = useRoute()
+  watch(
+    () => route.path,
+    () => {
+      nextTick(() => mediumZoom('.main img', { background: 'var(--vp-c-bg)' }))
+    },
+    { immediate: true }
+  )
+}