⬆️ version bump to v4.5

- Update obioptions.Version from "Release 4.4.29" to "/v/ Release v5"
- Update version.txt from 4.29 → .30
(automated by Makefile)

autodoc/docmd/pkg/obikmer/kmer_set_disk_ops.md

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+# Semantic Description of `obikmer` Set Operations
+
+This Go package implements scalable set operations over collections of *k*-mers stored in disk-backed, sorted structures (`.kdi` files). A `KmerSetGroup` represents a group of *N* disjoint sets (e.g., per-sample or per-partition), each containing sorted unique *k*-mers.
+
+## Core Set Operations
+
+- **`Union()`**: Computes the union across all *N* sets — a k-mer appears in output if present in ≥1 input set.
+- **`Intersect()`**: Computes the intersection — a k-mer appears only if present in *all* sets.
+- **`Difference()`**: Computes `set₀ \ (set₁ ∪ … ∪ setₙ₋₁)` — keeps k-mers unique to the first set.
+- **`QuorumAtLeast(q)`**: Returns k-mers present in ≥ *q* sets.
+- **`QuorumExactly(q)`**: Returns k-mers present in exactly *q* sets.
+- **`QuorumAtMost(q)`**: Returns k-mers present in ≤ *q* sets.
+
+## Pairwise Group Operations
+
+- **`UnionWith(other)` / `IntersectWith(other)`**: Performs *per-set* binary operations between two compatible groups (same k, m, partitions, size). Result has *N* sets: `setᵢ = this.setᵢ ⊕ other.setᵢ`, where ⊕ is union or intersection.
+
+## Implementation Highlights
+
+- **Partitioned & Parallelized**: Each operation processes partitions in parallel using `runtime.NumCPU()` workers.
+- **Streaming K-way Merge**: Uses efficient sorted-stream merging (via `KWayMerge`) to avoid loading full sets into memory.
+- **Quorum Filtering**: Counts occurrences per k-mer across partitions by merging sorted streams and tallying hits.
+- **Compatibility Check**: Ensures groups share metadata (k, m, partitions) before pairwise operations.
+- **Disk Output**: All results materialized as new `KmerSetGroup` in a directory, with per-partition `.kdi` files and metadata.
+
+All operations preserve sorted order and support large-scale genomic datasets via streaming, partitioning, and minimal memory footprint.