0.5.0

[0.5.0] - 2026-01-24

Mash auto-selection

• Added tree-aware pairwise Mash distance evaluation with early-stop pruning ("prove > threshold") and persistent caching under <out_dir>/logs/ to avoid recomputation across repeated runs.
• PlanUI: threshold modal (T) recomputes and reselects rounds; tree labels show Mash:…@source when the displayed distance originates from a descendant witness/max to avoid misinterpretation.
• CLI: optional prompt before computing Mash distances (includes leaf / max-pairs estimate) and stronger warning when mash is missing; supports caching remote sequences up front so Mash can run locally.