refactor(memory): extract shared MemorySummary count query and replace magic number

- Move duplicated Neo4j MemorySummary count query into
  MemoryBaseService.get_valid_memory_summary_count()
- Introduce MIN_MEMORY_SUMMARY_COUNT constant to replace hardcoded 5
- Fix import ordering in implicit_emotions_storage_repository
- Use UTC consistently for date calculations (remove CST offset,
  datetime.now → datetime.utcnow)

api/app/services/implicit_memory_service.py

@@ -34,6 +34,7 @@ from app.schemas.implicit_memory_schema import (
     UserMemorySummary,
 )
 from app.schemas.memory_config_schema import MemoryConfig
+from app.services.memory_base_service import MIN_MEMORY_SUMMARY_COUNT
 from sqlalchemy.orm import Session
 
 logger = logging.getLogger(__name__)
@@ -381,7 +382,7 @@ class ImplicitMemoryService:
 
     def _build_empty_profile(self) -> dict:
         """构建 MemorySummary 不足时返回的固定空白画像数据"""
-        now_ms = int(datetime.now().timestamp() * 1000)
+        now_ms = int(datetime.utcnow().timestamp() * 1000)
         insufficient = "Insufficient data for analysis"
 
         def _empty_dimension(name: str) -> dict:
@@ -442,17 +443,13 @@ class ImplicitMemoryService:
         
         try:
             # 前置检查：查询该用户有效的 MemorySummary 节点数量（排除孤立节点）
-            query = """
-            MATCH (n:MemorySummary)-[:DERIVED_FROM_STATEMENT]->(:Statement)
-            WHERE n.end_user_id = $end_user_id
-            RETURN count(DISTINCT n) as count
-            """
-            result = await self.neo4j_connector.execute_query(query, end_user_id=user_id)
-            memory_summary_count = result[0]["count"] if result and len(result) > 0 else 0
+            from app.services.memory_base_service import MemoryBaseService
+            base_service = MemoryBaseService()
+            memory_summary_count = await base_service.get_valid_memory_summary_count(user_id)
             logger.info(f"用户 MemorySummary 节点数量: {memory_summary_count} (user={user_id})")
 
-            if memory_summary_count < 5:
-                logger.info(f"MemorySummary 数量不足 5（当前 {memory_summary_count}），返回空白画像: user={user_id}")
+            if memory_summary_count < MIN_MEMORY_SUMMARY_COUNT:
+                logger.info(f"MemorySummary 数量不足 {MIN_MEMORY_SUMMARY_COUNT}（当前 {memory_summary_count}），返回空白画像: user={user_id}")
                 return self._build_empty_profile()
 
             # 并行调用4个分析方法

api/app/services/memory_base_service.py

@@ -265,12 +265,50 @@ async def Translation_English(modid, text, fields=None):
     # 其他类型（数字、布尔值、None等）：原样返回
     else:
         return text
+# 隐性记忆画像生成所需的最低 MemorySummary 节点数量
+MIN_MEMORY_SUMMARY_COUNT = 5
+
+
 class MemoryBaseService:
     """记忆服务基类，提供共享的辅助方法"""
     
     def __init__(self):
         self.neo4j_connector = Neo4jConnector()
     
+    async def get_valid_memory_summary_count(
+        self,
+        end_user_id: str
+    ) -> int:
+        """获取用户有效的 MemorySummary 节点数量（排除孤立节点）。
+
+        只统计存在 DERIVED_FROM_STATEMENT 关系的 MemorySummary 节点。
+
+        Args:
+            end_user_id: 终端用户ID
+
+        Returns:
+            有效 MemorySummary 节点数量
+        """
+        try:
+            query = """
+            MATCH (n:MemorySummary)-[:DERIVED_FROM_STATEMENT]->(:Statement)
+            WHERE n.end_user_id = $end_user_id
+            RETURN count(DISTINCT n) as count
+            """
+            result = await self.neo4j_connector.execute_query(
+                query, end_user_id=end_user_id
+            )
+            count = result[0]["count"] if result and len(result) > 0 else 0
+            logger.debug(
+                f"有效 MemorySummary 节点数量: {count} (end_user_id={end_user_id})"
+            )
+            return count
+        except Exception as e:
+            logger.error(
+                f"获取有效 MemorySummary 数量失败: {str(e)}", exc_info=True
+            )
+            return 0
+    
     @staticmethod
     def parse_timestamp(timestamp_value) -> Optional[int]:
         """

api/app/services/user_memory_service.py

@@ -21,7 +21,7 @@ from app.repositories.end_user_repository import EndUserRepository
 from app.repositories.neo4j.cypher_queries import Graph_Node_query
 from app.repositories.neo4j.neo4j_connector import Neo4jConnector
 from app.schemas.memory_episodic_schema import EmotionSubject, EmotionType, type_mapping
-from app.services.memory_base_service import MemoryBaseService
+from app.services.memory_base_service import MemoryBaseService, MIN_MEMORY_SUMMARY_COUNT
 from app.services.memory_config_service import MemoryConfigService
 from app.services.memory_perceptual_service import MemoryPerceptualService
 from app.services.memory_short_service import ShortService
@@ -1500,7 +1500,7 @@ async def analytics_memory_types(
     2. 工作记忆 (WORKING_MEMORY) = 会话数量（通过 ConversationRepository.get_conversation_by_user_id 获取）
     3. 短期记忆 (SHORT_TERM_MEMORY) = /short_term 接口返回的问答对数量
     4. 显性记忆 (EXPLICIT_MEMORY) = 情景记忆 + 语义记忆（通过 MemoryBaseService.get_explicit_memory_count 获取）
-    5. 隐性记忆 (IMPLICIT_MEMORY) = MemorySummary 节点数量（需 >= 5 才显示，否则为 0）
+    5. 隐性记忆 (IMPLICIT_MEMORY) = MemorySummary 节点数量（需 >= MIN_MEMORY_SUMMARY_COUNT 才显示，否则为 0）
     6. 情绪记忆 (EMOTIONAL_MEMORY) = 情绪标签统计总数（通过 MemoryBaseService.get_emotional_memory_count 获取）
     7. 情景记忆 (EPISODIC_MEMORY) = memory_summary（通过 MemoryBaseService.get_episodic_memory_count 获取）
     8. 遗忘记忆 (FORGET_MEMORY) = 激活值低于阈值的节点数（通过 MemoryBaseService.get_forget_memory_count 获取）
@@ -1557,20 +1557,12 @@ async def analytics_memory_types(
             logger.warning(f"获取会话数量失败，工作记忆数量设为0: {str(e)}")
             work_count = 0
     
-    # 获取隐性记忆数量（基于有关联关系的 MemorySummary 节点数量，需 >= 5 才计入）
+    # 获取隐性记忆数量（基于有关联关系的 MemorySummary 节点数量，需 >= MIN_MEMORY_SUMMARY_COUNT 才计入）
     implicit_count = 0
     if end_user_id:
         try:
-            # 只统计有 DERIVED_FROM_STATEMENT 关系的 MemorySummary 节点，排除孤立节点
-            query = """
-            MATCH (n:MemorySummary)-[:DERIVED_FROM_STATEMENT]->(:Statement)
-            WHERE n.end_user_id = $end_user_id
-            RETURN count(DISTINCT n) as count
-            """
-            result = await _neo4j_connector.execute_query(query, end_user_id=end_user_id)
-            memory_summary_count = result[0]["count"] if result and len(result) > 0 else 0
-            # 仅当 MemorySummary 节点数量 >= 5 时才显示数量，否则为 0
-            implicit_count = memory_summary_count if memory_summary_count >= 5 else 0
+            memory_summary_count = await base_service.get_valid_memory_summary_count(end_user_id)
+            implicit_count = memory_summary_count if memory_summary_count >= MIN_MEMORY_SUMMARY_COUNT else 0
             logger.debug(f"隐性记忆数量（有效MemorySummary节点数）: {implicit_count} (有效MemorySummary总数={memory_summary_count}, end_user_id={end_user_id})")
         except Exception as e:
             logger.warning(f"获取MemorySummary数量失败，隐性记忆数量设为0: {str(e)}")
@@ -1639,7 +1631,7 @@ async def analytics_memory_types(
         "WORKING_MEMORY": work_count,                             # 工作记忆（基于会话数量）
         "SHORT_TERM_MEMORY": short_term_count,                    # 短期记忆（基于问答对数量）
         "EXPLICIT_MEMORY": explicit_count,                        # 显性记忆（情景记忆 + 语义记忆）
-        "IMPLICIT_MEMORY": implicit_count,                        # 隐性记忆（MemorySummary节点数，需>=5）
+        "IMPLICIT_MEMORY": implicit_count,                        # 隐性记忆（MemorySummary节点数，需>=MIN_MEMORY_SUMMARY_COUNT）
         "EMOTIONAL_MEMORY": emotion_count,                        # 情绪记忆（使用情绪标签统计）
         "EPISODIC_MEMORY": episodic_count,                        # 情景记忆
         "FORGET_MEMORY": forget_count                             # 遗忘记忆（激活值低于阈值）