apps/docs: add /feat1 page

apps/docs/app/feat1/page.tsx

@@ -0,0 +1,30 @@
+"use client";
+
+import { useState } from "react";
+
+function ToggleContent({ children }: { children?: React.ReactNode }) {
+  const [show, setShow] = useState(false);
+  return (
+    <div>
+      <button onClick={() => setShow(!show)}>Toggle</button>
+      {show ? children : null}
+    </div>
+  );
+}
+
+export default function Page() {
+  return (
+    <>
+      <h1>Feat 1</h1>
+
+      <ToggleContent>
+        <p>
+          Lorem, ipsum dolor sit amet consectetur adipisicing elit. Dolorem,
+          voluptatem mollitia suscipit odio eos fugiat eum in molestias itaque
+          ex magni fuga deleniti dolores. Accusamus blanditiis reiciendis ab
+          quibusdam saepe.
+        </p>
+      </ToggleContent>
+    </>
+  );
+}