~anthropic/claude-sonnet-latest → A (8:1)

Side A fixes a real bug (zero-ratio votes silently defaulting to 1:1 instead of being rejected/dropped) and adds bounded validation consistently across the DSL parser, HTTP handler, and reducer, backed by new unit and integration regression tests. Side B is purely cosmetic renaming (canonical -> item/wire) with no behavioral change and no new tests, offering only marginal clarity value.