Introduce the `index` CLI subcommand, implementing a resumable, multi-stage pipeline to partition, dereplicate, and count kmers from input sequences. The command builds a layered de Bruijn graph index per partition, applies optional abundance filtering, and persists unitigs alongside an MPHF-based count matrix. Update `Cargo.toml` and `Cargo.lock` to include new dependencies (`epserde`, `ptr_hash`, `cacheline-ef`, `obicompactvec`, `obilayeredmap`) required for the index builder, and refresh the profiling data files.
Eric Coissac
e66c4d81ef