Flaky assert in test_lsm_vector_search_approximate_persistence: PQ search need not return the exact nearest embedding #131

tests/test_vector.py::TestLSMVectorIndex::test_lsm_vector_search_approximate_persistence asserts record.get("embedding") == [1.0, 0.0, 0.0] (added in #129). The test searches a PQ index, which is approximate, so the first row is not always the exact nearest vector. The Windows/amd64 Python 3.14 leg of #123, re-run on main after #129, failed with:

E   assert [0.009999999776482582, 0.10000000149011612, 0.10000000149011612] == [1.0, 0.0, 0.0]

Every PR can hit this until the assertion is relaxed.