fix(ui): add MarkdownContent component, fix deprecated meta tag, bump v0.9.2

- Add missing MarkdownContent component (ReactMarkdown + remarkGfm wrapper)
- Replace deprecated apple-mobile-web-app-capable with mobile-web-app-capable
- Bump version to 0.9.2

Assisted-by: GLM-5.1 via Crush <crush@charm.land>

web/src/components/Studio.jsx

@@ -277,6 +277,17 @@ function CodeBlockWithCopy({ part, index, copiedIdx, setCopiedIdx }) {
   )
 }
 
+function MarkdownContent({ content, raw }) {
+  if (raw) {
+    return <pre className="feed-content" style={{ whiteSpace: 'pre-wrap', fontFamily: 'var(--font-mono)', fontSize: '0.9em' }}>{content}</pre>
+  }
+  return (
+    <div className="feed-content">
+      <ReactMarkdown remarkPlugins={[remarkGfm]}>{content}</ReactMarkdown>
+    </div>
+  )
+}
+
 function FeedItem({ msg, activeAgents, onModeChange }) {
   const isUser = msg.role === 'user'
   const isSystem = msg.role === 'system'