fix(web): render custom HTML and Markdown content consistently (#5760)

* fix(markdown): render announcement markdown consistently

- support soft line breaks for announcement markdown without changing the default parser behavior.
- add explicit markdown element styles so lists, tables, code blocks, and quotes render correctly when typography styles are unavailable.
- apply the announcement markdown mode in both the popover and detail dialog for consistent display.

* refactor(markdown): simplify fallback markdown styles

- remove duplicate typography utility classes now covered by explicit markdown element fallbacks.
- keep the markdown renderer behavior unchanged while reducing class noise.
- modernize small helper expressions to satisfy targeted lint checks.

* fix(content): render custom HTML consistently

- add shared rich content rendering so custom HTML and Markdown use the same path across public pages and announcements.
- reuse common URL and HTML detection instead of duplicating content format checks per page.
- keep custom home content inside the standard public layout while preserving full-page iframe rendering for external URLs.

web/default/src/features/home/index.tsx

@@ -18,7 +18,7 @@ For commercial licensing, please contact support@quantumnous.com
 */
 import { useTranslation } from 'react-i18next'
 import { useAuthStore } from '@/stores/auth-store'
-import { Markdown } from '@/components/ui/markdown'
+import { RichContent } from '@/components/rich-content'
 import { PublicLayout } from '@/components/layout'
 import { Footer } from '@/components/layout/components/footer'
 import { CTA, Features, Hero, HowItWorks, Stats } from './components'
@@ -41,21 +41,24 @@ export function Home() {
   }
 
   if (content) {
+    if (isUrl) {
+      return (
+        <PublicLayout showMainContainer={false}>
+          <iframe
+            src={content}
+            className='h-screen w-full border-none'
+            title={t('Custom Home Page')}
+            sandbox='allow-forms allow-popups allow-popups-to-escape-sandbox allow-scripts'
+          />
+        </PublicLayout>
+      )
+    }
+
     return (
-      <PublicLayout showMainContainer={false}>
-        <main className='overflow-x-hidden'>
-          {isUrl ? (
-            <iframe
-              src={content}
-              className='h-screen w-full border-none'
-              title={t('Custom Home Page')}
-            />
-          ) : (
-            <div className='container mx-auto py-8'>
-              <Markdown className='custom-home-content'>{content}</Markdown>
-            </div>
-          )}
-        </main>
+      <PublicLayout>
+        <div className='mx-auto max-w-6xl px-4 py-8'>
+          <RichContent content={content} className='custom-home-content' />
+        </div>
       </PublicLayout>
     )
   }