Add global setting for default services, enable for preconfirmed accounts

Co-authored-by: Greg Karékinian <greg@karekinian.com>

app/models/setting.rb

@@ -206,4 +206,9 @@ class Setting < RailsSettings::Base
   #
   # field :email_imap_port, type: :string,
   #   default: ENV["EMAIL_IMAP_PORT"].presence || 993
+
+  def self.default_services
+    # TODO Make configurable from respective service settings page
+    %w[ discourse gitea mediawiki xmpp ]
+  end
 end