openai/gpt-chat-latest → B (5:1)

Side B introduces a new `RouteContext` abstraction in `server/src/html/routing.rs`, re-exports it from `html/mod.rs`, and centralizes scoped URL-building behind methods like `item_href`, `thread_url`, and `garden_root_url`, creating a reusable foundation for future routing changes. Side A only removes a `vote-compare-preview` HTML block from `garden.rs`, which is a localized UI cleanup with much narrower long-term impact.