Unifies bit and integer matrix storage into `PersistentBitMatrix` and `PersistentCompactIntMatrix` enums, supporting both columnar and memory-mapped single-file layouts. Introduces `LayerMeta` to persist layer dimensions as `layer_meta.json`, enabling correct initialization of implicit presence matrices. Adds CLI commands (`pack` and `--upgrade-index`) to convert existing columnar indices to the compact format and backfill missing metadata. Updates partitionner and layered map logic to use the new persistent builders, optimized memory allocation, and auto-detected storage backends.
Introduce parallel distance matrix generation using `ndarray` and `rayon` for both `BitMatrix` and `IntMatrix`. Adds full and additive-partial variants for Jaccard, Hamming, Bray-Curtis, Euclidean, and Hellinger metrics. Includes comprehensive unit tests verifying matrix symmetry, zero diagonals, and numerical correctness against pairwise calculations.
Introduce the `obicompactvec` crate, featuring a two-tier, memory-mapped integer vector that uses a primary `u8` array with a sentinel for overflow dispatch and a sparse L1-resident index for fast random access. Implement builder and reader modules with zero-copy serialization and comprehensive test coverage. Update `obilayeredmap` to replace the default hash function with a cache-line-optimized `Mphf`, adding explicit bounds checking and duplicate-slot detection. Add documentation for both modules and update project configuration files accordingly.