fix: 解决消息重复问题

app-android/app/src/main/java/com/huaga/life_echo/data/repository/MessageRepository.kt

@@ -19,10 +19,11 @@ class MessageRepository(
         return messageDao.getMessagesByConversationId(conversationId)
     }
     
-    /** 从 [conversationApi] 拉取消息并写入本地数据库 */
+    /** 从 [conversationApi] 拉取消息并写入本地数据库，以服务端为准替换该会话的本地消息，避免与本地临时消息重复显示 */
     suspend fun syncMessages(conversationId: String) {
         val result = conversationApi.getMessages(conversationId)
         result.getOrNull()?.let { messages ->
+            messageDao.deleteMessagesByConversationId(conversationId)
             val dbMessages = messages.map { dto ->
                 Message(
                     id = dto.id,

app-android/app/src/main/java/com/huaga/life_echo/ui/viewmodel/CreateMemoryViewModel.kt

@@ -658,12 +658,26 @@ class CreateMemoryViewModel(
                     isTyping.value = false
                 }
 
+                // 用 [SPLIT] 拼接多条，与后端约定一致，便于 UI 按 [SPLIT] 拆成多个气泡
+                if (index == 0) {
+                    agentResponse.value = text
+                } else {
+                    agentResponse.value += "[SPLIT]$text"
+                }
+
+                // 仅在完整收到一条 AI 回复时插入一次，避免按 index 多次插入导致同一条显示多遍
+                if (index >= total - 1) {
+                    isStreaming.value = false
+                    streamingText.value = ""
+                    isTyping.value = false
+                    conversationRealtime.setGenerating(false)
                     conversationId.value?.let { id ->
                         val messageTimestamp = System.currentTimeMillis()
+                        val fullContent = agentResponse.value
                         val aiMessage = Message(
-                        id = "ai_${System.currentTimeMillis()}_$index",
+                            id = "ai_${System.currentTimeMillis()}",
                             conversationId = id,
-                        content = text,
+                            content = fullContent,
                             senderType = "assistant",
                             timestamp = messageTimestamp,
                             messageType = "text"
@@ -672,23 +686,11 @@ class CreateMemoryViewModel(
                             messageRepository.insertMessage(aiMessage)
                             updateConversationLatestMessage(
                                 conversationId = id,
-                            messagePreview = text,
+                                messagePreview = fullContent,
                                 timestamp = messageTimestamp,
                             )
                         }
                     }
-
-                if (index == 0) {
-                    agentResponse.value = text
-                } else {
-                    agentResponse.value += "\n\n$text"
-                }
-
-                if (index >= total - 1) {
-                    isStreaming.value = false
-                    streamingText.value = ""
-                    isTyping.value = false
-                    conversationRealtime.setGenerating(false)
                 }
             }
             MessageType.agent_response_start -> {