Introduces `TempCompactIntVec` and `TempBitVec` as temporary, file-backed intermediates to replace eager in-memory vectors, enabling OS-level paging under memory pressure. Updates the `MatrixGroupOps` trait to return `io::Result` types, allowing proper error propagation and supporting chunked accumulation for large column groups. Includes builder patterns with `.freeze()` finalization, automatic `TempDir` cleanup on drop, and necessary test updates to handle the new fallible signatures. Also fixes `Cargo.toml` section ordering.
Add Mermaid diagrams to visualize the trait hierarchy, compact int storage layout, and SIMD-vectorizable arithmetic operations for MemoryIntVec and PersistentCompactIntVec. Also document concrete type structures and planned layer/partition composition rules to improve documentation clarity.
Document the two-tier compact integer encoding, BitSlice/IntSlice trait hierarchy, and SIMD-friendly O(n+k) algorithms. Include details on concrete memory and persistent vector types, matrix aggregation traits, and planned group-filtering APIs.
Eric Coissac