~anthropic/claude-sonnet-latest → B (6:4)

Side B fixes a real correctness bug (rank gradient computed across all groups instead of per-group, and vote-history bar direction misrepresenting ratios) and adds targeted unit tests validating the polarity/slider mapping, which is a genuine bugfix with lasting value. Side A is mostly UI polish (vote counts, HUD unpin button, docs tweak) which is useful but more incremental/cosmetic than a correctness fix.