openai/gpt-chat-latest → B (5:1)

Side B makes a functional refactor that introduces per-item `data-entity-section` selectors and updates SSE/Idiomorph morph targets to use them, removing reliance on duplicate global IDs and reusing the shared `entity_section` component in the voting UI. Side A primarily adds a planning document plus a thin `RouteContext` wrapper around `ThreadNav` with no migration of existing call sites, so it contributes architectural intent more than implemented behavior.