Replace in-memory hashing with a disk-backed external merge sort and `PersistentCompactIntVec` to drastically reduce peak RAM. Unify both phases using a custom `PtrHash` MPHF, eliminating `GOFunction` and `boomphf`. Introduce a concrete three-step `count_partition()` pipeline with adaptive chunk sizing based on available system memory. Update dependencies to `memmap2`, `ptr_hash`, and `obicompactvec`. Additionally, document strict genomics-only memory constraints and enforce an architectural feedback workflow requiring explicit user authorization before structural changes.
Formalize the two-phase MPHF indexing architecture and update Phase 6 to use `evidence.bin` for direct kmer extraction. Simplify the evidence and unitig storage layouts to flat packed formats enabling O(1) random access. Introduce aggregation traits (`ColumnWeights`, `CountPartials`, `BitPartials`) to support additive distance metric decomposition across partitions. Narrow the documented scope from metagenomic to individual genome datasets, and replace speculative open questions with concrete implementation specifications.
Eric Coissac