refactor(frontend): migrate from Vite to Nuxt SPA

Replace Vite and Vue Router with Nuxt framework
Update Docker, build scripts, and env vars for Nuxt generate

frontend/pages/disclaimers.vue

@@ -0,0 +1,12 @@
+<script setup lang="ts">
+import LegalView from '../src/views/LegalView.vue';
+
+definePageMeta({
+  name: 'disclaimers',
+  seo: { titleKey: 'pages.legal.disclaimers.title', descriptionKey: 'pages.legal.disclaimers.subtitle', canonicalPath: '/disclaimers' }
+});
+</script>
+
+<template>
+  <LegalView page="disclaimers" />
+</template>