Apply batched suggestions from code review

Co-authored-by: Roman <dev@rman.dev>

domains/_cf-custom-hostname.kimjinwoo.json

@@ -1,5 +1,4 @@
 {
-  "name": "_cf-custom-hostname.kimjinwoo",
   "description": "Cloudflare custom hostname verification for OpenAI Sites",
   "owner": {
     "username": "K-im-jinwoo"

domains/_openai-site-verification.kimjinwoo.json

@@ -1,5 +1,4 @@
 {
-  "name": "_openai-site-verification.kimjinwoo",
   "description": "OpenAI Sites domain ownership verification",
   "owner": {
     "username": "K-im-jinwoo"

domains/kimjinwoo.json

@@ -1,5 +1,4 @@
 {
-  "name": "kimjinwoo",
   "description": "Personal portfolio for business and AI automation development",
   "owner": {
     "username": "K-im-jinwoo"