Redis HNSW EF_RUNTIME: the library default (not set by Spring AI) against explicit values; index rebuilt and reloaded each time
ef_runtime    recall@10    p50 ms  filt recall    filt p50 ms
default           0.616       0.6        1.000            1.6
50                0.962       0.6        1.000            1.3
200               1.000       0.8        1.000            1.3
