feat(pages): add web development services page

This commit introduces a new page at `/webDev` to display web development services and pricing plans.

To support this, a new reusable composable `useLocalizedCollection` has been created to simplify fetching localized content from Nuxt
Content. The index page has been refactored to use this new composable.

- Adds `webDev.vue` page and corresponding `webDev.yml` content files for EN and ZH.
- Defines a Zod schema in `content.config.ts` for the new content type.
- Updates the navigation link to point to the new page.

app/pages/index.vue

@@ -71,47 +71,7 @@
 </template>
 
 <script lang="ts" setup>
-import type { Collections } from "@nuxt/content";
-
-const { locale } = useI18n();
-
-const { data: page } = await useAsyncData(
-  "index-" + locale.value,
-  async () => {
-    // Build collection name based on current locale
-    let localeSuffix = "";
-    switch (locale.value) {
-      case "en":
-        localeSuffix = "en";
-        break;
-      case "zh-CN":
-        localeSuffix = "zh";
-        break;
-      default:
-        localeSuffix = "en";
-        break;
-    }
-    const collection = ("index_" + localeSuffix) as keyof Collections;
-    const content = await queryCollection(collection).first();
-
-    // Optional: fallback to default locale if content is missing
-    if (!content && locale.value !== "en") {
-      return await queryCollection("index_en").first();
-    }
-
-    return content;
-  },
-  {
-    watch: [locale], // Refetch when locale changes
-  }
-);
-if (!page.value) {
-  throw createError({
-    statusCode: 404,
-    statusMessage: `Page not found, the index_${locale.value} couldn't be found.`,
-    fatal: true,
-  });
-}
+const { data: page } = await useLocalizedCollection("index");
 
 useSeoMeta({
   title: page.value?.seo.title,