feat: add research decks with WebMCP controls

src/components/post-text.tsx

@@ -0,0 +1,49 @@
+import type { ReactNode } from 'react'
+
+const URL = /(https?:\/\/[^\s]+)/g
+const HTML_ENTITY = /&(?:#(\d+)|#x([\da-f]+)|amp|apos|gt|lt|quot);/gi
+const NAMED_ENTITIES: Record<string, string> = {
+  '&amp;': '&',
+  '&apos;': "'",
+  '&gt;': '>',
+  '&lt;': '<',
+  '&quot;': '"',
+}
+function decodeHtmlEntities(text: string): string {
+  return text.replace(HTML_ENTITY, (entity, decimal, hexadecimal) => {
+    if (!decimal && !hexadecimal) {
+      return NAMED_ENTITIES[entity.toLowerCase()] ?? entity
+    }
+
+    const codePoint = Number.parseInt(decimal ?? hexadecimal, decimal ? 10 : 16)
+    return codePoint <= 0x10ffff ? String.fromCodePoint(codePoint) : entity
+  })
+}
+
+function linkedText(text: string): ReactNode[] {
+  const decoded = decodeHtmlEntities(text)
+  const parts: ReactNode[] = []
+  let cursor = 0
+  for (const match of decoded.matchAll(URL)) {
+    const href = match[0]
+    const start = match.index
+    if (start > cursor) parts.push(decoded.slice(cursor, start))
+    parts.push(
+      <a
+        href={href}
+        key={`link-${start}`}
+        rel="noreferrer noopener"
+        target="_blank"
+      >
+        {href}
+      </a>,
+    )
+    cursor = start + href.length
+  }
+  if (cursor < decoded.length) parts.push(decoded.slice(cursor))
+  return parts
+}
+
+export function PostText({ text }: { text: string }) {
+  return <>{linkedText(text)}</>
+}