Unify page layouts, compact headers and shared UI styling

frontend/app/changelog/page.tsx

@@ -1,5 +1,7 @@
 'use client'
 
+import PageHeading from '../ui/PageHeading'
+
 import { useEffect, useMemo, useState } from 'react'
 import { useRouter } from 'next/navigation'
 import { authFetch, clearToken, getApiBase, getToken } from '../lib/auth'
@@ -106,14 +108,9 @@ export default function ChangelogPage() {
   }, [groups, loading])
 
   return (
-    <div className="page">
-      <section className="card changelog-card">
-        <div className="changelog-header">
-          <h1>Changelog</h1>
-          <p className="lede">Latest updates and release notes.</p>
-        </div>
-        {content}
-      </section>
-    </div>
+    <main className="card changelog-page">
+      <PageHeading title="Changelog" description="What’s new and improved in Magent." />
+      {content}
+    </main>
   )
 }