fix memory index bug

Author: yaozheng-fang

veadk/knowledgebase/knowledgebase.py

@@ -84,6 +84,7 @@ class KnowledgeBase(BaseModel):
     def model_post_init(self, __context: Any) -> None:
         if isinstance(self.backend, BaseKnowledgebaseBackend):
             self._backend = self.backend
+            self.index = self._backend.index
             logger.info(
                 f"Initialized knowledgebase with provided backend instance {self._backend.__class__.__name__}"
             )

veadk/memory/long_term_memory.py

@@ -96,6 +96,7 @@ def model_post_init(self, __context: Any) -> None:
         # Once user define a backend instance, use it directly
         if isinstance(self.backend, BaseLongTermMemoryBackend):
             self._backend = self.backend
+            self.index = self._backend.index
             logger.info(
                 f"Initialized long term memory with provided backend instance {self._backend.__class__.__name__}"
             )