feat: slightly adjust similarity threshold for returned memories

Author: CaralHsi

src/memos/mem_os/product.py

@@ -693,7 +693,7 @@ def run_async_in_thread():
             thread.start()
 
     def _filter_memories_by_threshold(
-        self, memories: list[TextualMemoryItem], threshold: float = 0.50, min_num: int = 3
+        self, memories: list[TextualMemoryItem], threshold: float = 0.52, min_num: int = 0
     ) -> list[TextualMemoryItem]:
         """
         Filter memories by threshold.