Fix exception for NIP-05 JSON of "_" with relay configured

app/controllers/well_known_controller.rb

@@ -9,15 +9,13 @@ class WellKnownController < ApplicationController
     if params[:name] == "_"
       # pubkey for the primary domain without a username (e.g. kosmos.org)
       res = { names: { "_": Setting.nostr_public_key } }
+      res[:relays] = { "_" => [ relay_url ] } if relay_url
     else
       @user = User.where(cn: params[:name], ou: domain).first
       http_status :not_found and return if @user.nil? || @user.nostr_pubkey.blank?
 
       res = { names: { @user.cn => @user.nostr_pubkey } }
-    end
-
-    if relay_url
-      res[:relays] = { @user.nostr_pubkey => [ relay_url ] }
+      res[:relays] = { @user.nostr_pubkey => [ relay_url ] } if relay_url
     end
 
     respond_to do |format|