bm25 crate.avgdl argument to usersunicode-segmentation to 1.12.0, since 1.13+ requires rustc 1.85 and raises
the effective MSRV above the package's stated rust-versionstore()/load() now save the corpus and BM25 parameters and rebuild the engine
on load, rather than serializing the engine directly; bm25 2.3.2 does not
implement serde::Serialize/Deserialize for SearchEngineextendr and uses rextendr::vendor_pkgs(overwrite=TRUE) for
vendoring rust dependencies.released on CRAN