ui: remove source attribution + publisher rights notice

src/app/article/[slug]/page.tsx

@@ -59,7 +59,6 @@ export async function generateMetadata({
       images: a.image
         ? [{ url: a.image, width: 1200, height: 630, alt: title }]
         : [{ url: '/og-image.png', width: 1200, height: 630, alt: 'MapleBrief' }],
-      authors: [a.siteName],
     },
     twitter: {
       card: 'summary_large_image',
@@ -94,7 +93,6 @@ export default async function ArticlePage({
               <span className="rounded bg-maple-600/10 px-2 py-0.5 text-xs font-bold uppercase tracking-wide text-maple-700">
                 {SECTIONS.find((s) => s.slug === a.category)?.label ?? 'Briefing'}
               </span>
-              <span className="text-ink-500">via {a.siteName}</span>
               {a.publishedAt && (
                 <span className="text-ink-400">· {formatFull(a.publishedAt.toISOString())}</span>
               )}