fix: chat memory extraction crashes on a non-dict message (#1749)

tests/test_memory_extract_chat_nondict.py

@@ -0,0 +1,15 @@
+from src.memory import MemoryManager
+
+
+def test_extract_memory_from_chat_skips_non_dict_messages(tmp_path):
+    # chat_history rows can be malformed (a non-dict slipping in from a partial
+    # session blob); the old loop did msg.get(...) and crashed on the first one.
+    m = MemoryManager(str(tmp_path))
+    history = [
+        {"role": "assistant", "content": "- remember to buy milk"},
+        "junk-msg",
+        None,
+        {"role": "user", "content": "hi"},
+    ]
+    out = m.extract_memory_from_chat(history)
+    assert any(e["text"] == "remember to buy milk" for e in out)