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/webDev.vue

@@ -0,0 +1,23 @@
+<template>
+  <UContainer>
+    <UPageHero :title="page?.title" :description="page?.description" />
+
+    <p class="text-muted py-4 text-center">{{ page?.remarks }}</p>
+
+    <UTabs :items="page?.services.map((s) => ({ ...s, slot: s.id }))">
+      <template
+        v-for="service in page?.services"
+        :key="service.id"
+        #[service.id]
+      >
+        <UPricingPlans :plans="service.plans" />
+      </template>
+    </UTabs>
+  </UContainer>
+</template>
+
+<script lang="ts" setup>
+const { data: page } = await useLocalizedCollection("webDev");
+</script>
+
+<style></style>