fix(character): 캐릭터 상세 조회 응답에 MBTI·성별·나이 필드 추가

- CharacterDetailResponse에 gender, age 필드 추가
- ChatCharacterController에서 gender, age 매핑
- 기존 엔티티(ChatCharacter)의 gender/age 활용

src/main/kotlin/kr/co/vividnext/sodalive/chat/character/controller/ChatCharacterController.kt

@@ -175,6 +175,8 @@ class ChatCharacterController(
                 name = character.name,
                 description = character.description,
                 mbti = character.mbti,
+                gender = character.gender,
+                age = character.age,
                 imageUrl = "$imageHost/${character.imagePath ?: "profile/default-profile.png"}",
                 personalities = personality,
                 backgrounds = background,

src/main/kotlin/kr/co/vividnext/sodalive/chat/character/dto/CharacterDetailResponse.kt

@@ -8,6 +8,8 @@ data class CharacterDetailResponse(
     val name: String,
     val description: String,
     val mbti: String?,
+    val gender: String?,
+    val age: Int?,
     val imageUrl: String,
     val personalities: CharacterPersonalityResponse?,
     val backgrounds: CharacterBackgroundResponse?,