Redesign admin accounts index (#9340)

* Improve overview of accounts in admin UI

- Display suspended status, role, last activity and IP prominently
- Default to showing local accounts
- Default to not showing suspended accounts

* Remove unused strings

* Fix tests

* Allow filtering accounts by IP mask

config/locales/io.yml

@@ -44,10 +44,6 @@ io:
       most_recent_activity: Most recent activity
       most_recent_ip: Most recent IP
       not_subscribed: Not subscribed
-      order:
-        alphabetic: Alphabetic
-        most_recent: Most recent
-        title: Order
       perform_full_suspension: Perform full suspension
       profile_url: Profile URL
       public: Public