feat(06-04): add BlogPrevNext component (grid 2 cols, BlogCard compact variant)

app/components/BlogPrevNext.vue

@@ -0,0 +1,39 @@
+<script setup lang="ts">
+interface SurroundArticle {
+  path: string
+  title: string
+  description?: string
+  date: string
+  tags?: string[]
+  image?: string
+  minutes?: number
+}
+
+interface Props {
+  prev: SurroundArticle | null
+  next: SurroundArticle | null
+}
+
+defineProps<Props>()
+const { t } = useI18n()
+</script>
+
+<template>
+  <nav
+    v-if="prev || next"
+    class="mt-16 grid md:grid-cols-2 gap-5"
+    :aria-label="t('blog.prevArticle') + ' / ' + t('blog.nextArticle')"
+  >
+    <!-- Prev (older article in DESC order) -->
+    <div v-if="prev">
+      <BlogCard :article="prev" variant="compact" direction="prev" />
+    </div>
+    <div v-else aria-hidden="true" />
+
+    <!-- Next (newer article in DESC order) -->
+    <div v-if="next">
+      <BlogCard :article="next" variant="compact" direction="next" />
+    </div>
+    <div v-else aria-hidden="true" />
+  </nav>
+</template>