번역 텍스트 개선

- 영문 validation 메시지 소문자로 통일
- 한글 고객지원, 1:1문의 띄어쓰기 제거

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

src/locales/en.json

@@ -158,12 +158,12 @@
                 "03": "Completed"
             },
             "validation": {
-                "title": "Title is Required.",
-                "requestType": "RequestType is Required.",
-                "requestName": "RequestName is Required.",
-                "requestTel": "Phone number is Required.",
-                "requestEmail": "Invalid Email Type.",
-                "contents": "Contents is Required."
+                "title": "Title is required.",
+                "requestType": "RequestType is required.",
+                "requestName": "RequestName is required.",
+                "requestTel": "Phone number is required.",
+                "requestEmail": "Invalid email type.",
+                "contents": "Contents is required."
             }
         }
     },