Add post edited notice in admin and public UIs (#17335)

* Add edited toot flag on public pages

* Add toot edit flag to admin pages

app/views/admin/reports/_status.html.haml

@@ -27,6 +27,9 @@
         ·
       = link_to ActivityPub::TagManager.instance.url_for(status), class: 'detailed-status__datetime', target: stream_link_target, rel: 'noopener noreferrer' do
         %time.formatted{ datetime: status.created_at.iso8601, title: l(status.created_at) }= l(status.created_at)
+      - if status.edited?
+        ·
+        = t('statuses.edited_at', date: l(status.edited_at))
       - if status.discarded?
         ·
         %span.negative-hint= t('admin.statuses.deleted')