fix(tags): guard generateStaticParams against empty content dir

app/tags/[tag]/page.tsx

@@ -12,6 +12,9 @@ export const dynamic = 'force-static'
 
 export async function generateStaticParams() {
   const tags = await getAllTags()
+  if (tags.length === 0) {
+    return [{ tag: '__no-tags__' }]
+  }
   return tags.map((tag) => ({ tag: tag.slug }))
 }
 
@@ -27,6 +30,9 @@ export async function generateMetadata({ params }: TagPageProps): Promise<Metada
 
 export default async function TagPage({ params }: TagPageProps) {
   const slug = (await params).tag
+
+  if (slug === '__no-tags__') notFound()
+
   const tags = await getAllTags()
   const tag = tags.find((item) => item.slug === slug)