openai/gpt-chat-latest → B (20:1)

Side B is a major architectural refactor that consolidates many REST endpoints into a batch RPC API, introduces room-scoped commands and data models (room/thread separation), extracts validation into a reusable module, updates reducer/event structures, and migrates the CLI and tests to the new protocol. Side A only removes a heading and changes a disabled paginator element from a <span> to an inert <a>, which is a minor UI tweak with little lasting impact.