fix: support list of numpy f16 floats as query vector (#1931)

User reported on Discord, when using
`table.vector_search([np.float16(1.0), np.float16(2.0), ...])`, it
yields `TypeError: 'numpy.float16' object is not iterable`

python/python/tests/test_query.py

@@ -3,6 +3,7 @@
 
 import unittest.mock as mock
 from datetime import timedelta
+from pathlib import Path
 
 import lancedb
 from lancedb.index import IvfPq
@@ -384,3 +385,19 @@ async def test_query_to_list_async(table_async: AsyncTable):
     assert len(list) == 2
     assert list[0]["vector"] == [1, 2]
     assert list[1]["vector"] == [3, 4]
+
+
+@pytest.mark.asyncio
+async def test_query_with_f16(tmp_path: Path):
+    db = await lancedb.connect_async(tmp_path)
+    f16_arr = np.array([1.0, 2.0, 3.0, 4.0], dtype=np.float16)
+
+    df = pa.table(
+        {
+            "vector": pa.FixedSizeListArray.from_arrays(f16_arr, 2),
+            "id": pa.array([1, 2]),
+        }
+    )
+    tbl = await db.create_table("test", df)
+    results = await tbl.vector_search([np.float16(1), np.float16(2)]).to_pandas()
+    assert len(results) == 2