Fix self-host migrations and first admin setup

supabase/migrations/0009_lock_registration_after_first_admin.sql

@@ -37,3 +37,11 @@ begin
   return new;
 end;
 $$;
+
+drop trigger if exists on_auth_user_created on auth.users;
+
+create trigger on_auth_user_created
+  after insert on auth.users
+  for each row execute procedure public.handle_new_user();
+
+notify pgrst, 'reload schema';