openai/gpt-chat-latest → B (4:3)

Side B adds several concrete, reusable capabilities: an asynchronous JSONL `EventLog` with append/load logic and error handling, a persistent `ViewStore` that flushes counts to disk, plus deployment artifacts (`Dockerfile` and `fly.toml`) that enable building and running the project. Side A mostly introduces a detailed migration plan document and a thin `RouteContext` wrapper around `ThreadNav` with re-exports; while directionally useful, it is largely scaffolding and documentation rather than completed functionality.