Merge branch 'refactor/backend-architecture' into development

api/app/features/memory/extractor.py

@@ -0,0 +1,6 @@
+"""Entity / event / fact extraction from chunks (skeleton)."""
+
+
+async def extract_facts(chunk_text: str, *, user_id: str) -> list[dict]:
+    """Extract structured facts from a text chunk using LLM."""
+    raise NotImplementedError