huspm-datasets: quantitative sequence databases for high-utility sequential pattern mining

Quantitative sequence databases used across several high-utility sequential pattern mining studies, so that each measures on exactly the same bytes. The sequence structure comes from the public SPMF datasets, which carry no utilities; internal quantities and external profits are generated deterministically by SPMF_Converter with a fixed seed and a per-file random stream, so a given raw file converts to the same bytes regardless of what else is converted alongside it. Each release ships a tarball and a SHA-256 manifest so a study can pin the exact data it measured on.