~anthropic/claude-sonnet-latest → A (60:40)

Side A completes a substantial, well-documented type-safety refactor (CanonicalItemUrl -> ItemId) across the whole codebase with consistent updates to reducer, ranking, RPC, HTML, and tests, removing a stringly-typed newtype in favor of a structured enum with proper serde/Ord semantics. Side B adds a real feature (vote comparison UI with morph updates, pair-selection logic, and tests) which is valuable but narrower in scope and more localized to one UI flow, making it a good but less foundational contribution than A's systemic identity-model overhaul.