feat(memory): 使用异步初始化确保统一记忆管理器已准备就绪

src/chat/replyer/default_generator.py

@@ -598,12 +598,14 @@ class DefaultReplyer:
             return ""
 
         try:
-            from src.memory_graph.manager_singleton import get_unified_memory_manager
+            from src.memory_graph.manager_singleton import (
+                ensure_unified_memory_manager_initialized,
+            )
             from src.memory_graph.utils.three_tier_formatter import memory_formatter
 
-            unified_manager = get_unified_memory_manager()
+            unified_manager = await ensure_unified_memory_manager_initialized()
             if not unified_manager:
-                logger.debug("[三层记忆] 管理器未初始化")
+                logger.debug("[三层记忆] 管理器初始化失败或未启用")
                 return ""
 
             # 目标查询改为使用最近多条消息的组合块