Widen the doc detail view to max-w-5xl

Matches the width already used on the run and new-run cards.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

src/app/(app)/docs/[slug]/page.tsx

@@ -27,7 +27,7 @@ export default async function DocPage({ params }: DocPageProps) {
   if (content === null) notFound();
 
   return (
-    <div className="mx-auto flex max-w-3xl flex-col gap-6">
+    <div className="mx-auto flex max-w-5xl flex-col gap-6">
       <Link
         href="/docs"
         className="text-muted-foreground hover:text-foreground flex w-fit items-center gap-1 text-sm"