feat: expose the vector rerank method in the CypherEngine API

[ChunxuTang]

This PR exposes the vector rerank method in the CypherEngine API, similar to the existing CypherQuery API.

An example:

engine = CypherEngine(config, datasets)

results = engine.execute_with_vector_rerank(
    "MATCH (d:Document) WHERE d.category = 'tech' RETURN d.id, d.name, d.embedding",
    VectorSearch("d.embedding")
    .query_vector([1.0, 0.0, 0.0])
    .metric(DistanceMetric.L2)
    .top_k(2),
)

data = results.to_pydict()

[codecov-commenter]

Codecov Report

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