Add moderation warnings (#9519)

* Add moderation warnings

Replace individual routes for disabling, silencing, and suspending
a user, as well as the report update route, with a unified account
action controller that allows you to select an action (none,
disable, silence, suspend) as well as whether it should generate an
e-mail notification with optional custom text. That notification,
with the optional custom text, is saved as a warning.

Additionally, there are warning presets you can configure to save
time when performing the above.

* Use Account#local_username_and_domain

config/locales/es.yml

@@ -433,12 +433,6 @@ es:
       last_delivery: Última entrega
       title: WebSub
       topic: Tópico
-    suspensions:
-      bad_acct_msg: El valor de confirmación no cuadra. ¿Estás suspendiendo la cuenta correcta?
-      hint_html: 'Para confirmar las suspensión de la cuenta, por favor introduce %{value} en el campo de abajo:'
-      proceed: Proceder
-      title: Suspender %{acct}
-      warning_html: 'Suspender esta cuenta borrará <strong>irreversiblemente</strong> los datos de stra cuenta que incluyen:'
     title: Administración
   admin_mailer:
     new_report: