Add notification policies and notification requests (#29366)

app/services/accept_notification_request_service.rb

@@ -0,0 +1,8 @@
+# frozen_string_literal: true
+
+class AcceptNotificationRequestService < BaseService
+  def call(request)
+    NotificationPermission.create!(account: request.account, from_account: request.from_account)
+    UnfilterNotificationsWorker.perform_async(request.id)
+  end
+end