fix(chat): DM 푸시 제목 키를 분리한다

src/main/kotlin/kr/co/vividnext/sodalive/i18n/SodaMessageSource.kt

@@ -1175,6 +1175,11 @@ class SodaMessageSource {
             Lang.EN to "You have received a DM from %s.",
             Lang.JA to "%sからDMが届きました。"
         ),
+        "message.fcm.dm_title" to mapOf(
+            Lang.KO to "DM",
+            Lang.EN to "DM",
+            Lang.JA to "DM"
+        ),
         "message.fcm.voice_received" to mapOf(
             Lang.KO to "%s님으로 부터 음성메시지가 도착했습니다.",
             Lang.EN to "You have received a voice message from %s.",

src/main/kotlin/kr/co/vividnext/sodalive/v2/usercreatorchat/service/UserCreatorChatService.kt

@@ -226,11 +226,16 @@ class UserCreatorChatService(
         } else {
             "message.fcm.dm_received"
         }
+        val titleKey = if (messageKey == "message.fcm.dm_received") {
+            "message.fcm.dm_title"
+        } else {
+            "message.fcm.title"
+        }
         applicationEventPublisher.publishEvent(
             FcmEvent(
                 type = FcmEventType.INDIVIDUAL,
                 category = PushNotificationCategory.MESSAGE,
-                titleKey = "message.fcm.title",
+                titleKey = titleKey,
                 messageKey = messageKey,
                 senderMemberId = sender.id,
                 args = listOf(sender.nickname),