fix: _extract_entities crashes on a non-string query (#1724)

tests/test_search_query_entities_nonstring.py

@@ -0,0 +1,15 @@
+from services.search.query import _extract_entities
+
+
+def test_extract_entities_handles_non_string_query():
+    # _detect_question_type already guards non-strings, but the function then
+    # runs re.findall over `query` directly, which raises TypeError on a
+    # non-string. A non-str query should yield no entities.
+    assert _extract_entities(None) == {"names": [], "dates": []}
+    assert _extract_entities(123) == {"names": [], "dates": []}
+
+
+def test_extract_entities_still_finds_names_and_years():
+    out = _extract_entities("What did Alice do in 2024")
+    assert "Alice" in out["names"]
+    assert "2024" in out["dates"]