Add customizable user roles (#18641)

* Add customizable user roles

* Various fixes and improvements

* Add migration for old settings and fix tootctl role management

app/lib/admin/system_check/rules_check.rb

@@ -3,6 +3,10 @@
 class Admin::SystemCheck::RulesCheck < Admin::SystemCheck::BaseCheck
   include RoutingHelper
 
+  def skip?
+    !current_user.can?(:manage_rules)
+  end
+
   def pass?
     Rule.kept.exists?
   end