fix(docs): build failed

docs/astro.config.ts

@@ -5,6 +5,29 @@ import UnoCSS from 'unocss/astro'
 // https://astro.build/config
 export default defineConfig({
   site: 'https://airi.build',
+  vite: {
+    // This kind of error occurs when building astro site:
+    // The requested module 'nanoid/non-secure' does not provide an export named 'default'
+    // 12:51:31 AM:   Location:
+    // 12:51:31 AM:     /opt/build/repo/node_modules/.pnpm/astro@5.10.1_@types+node@24.0.4_encoding@0.1.13_jiti@2.4.2_less@4.3.0_lightningcss@1.30_07650979d98d2e2072de2da1f022c9b9/node_modules/astro/dist/core/build/pipeline.js:221:15
+    //
+    // Discovered these issues:
+    //
+    // [Build Error] The requested module 'x' does not provide an export named 'default' · Issue #8660 · withastro/astro
+    // https://github.com/withastro/astro/issues/8660
+    //
+    // Related to:
+    //
+    // - Issue when importing default from module on SSR https://github.com/vitejs/vite/issues/10712
+    // - CJS named imports in an ESM library https://github.com/vitejs/vite/issues/14332
+    //
+    // This is because somehow postcss related script is imported,
+    // and import require$$0$2 from 'nanoid/non-secure' will be
+    // generated, while nanoid/non-secure does not have a default export.
+    ssr: {
+      noExternal: ['nanoid'],
+    },
+  },
   integrations: [
     UnoCSS(),
     starlight({