Introduces batch retrieval and sub-matrix extraction methods across vector, view, reader, and matrix types. These implementations optimize cache locality by sorting requested indices for sequential memory access before applying an inverse permutation to restore original order. Includes allocation-free variants that populate caller-provided buffers. Updates architecture documentation to define sibling annex persistence in iteration order and clarify pipeline separation.
Introduces `index` and `index_batch` methods for direct MPHF slot mapping without membership validation, alongside four public iterator methods for deterministic traversal of canonical kmers. These are backed by dedicated `KmerIter` and `KmerBatchIter` structs that wrap the underlying unitig file reader. Updates `LayerEvidence::Approx` to eagerly open the unitig reader during initialization, enforcing a clear separation between raw mapping and verified lookup workflows.
Eric Coissac