openai/gpt-chat-latest → A (4:1)

Side A strengthens the project's type safety by changing `resolve_item` to return `CanonicalItemUrl` instead of `String`, propagating canonical URL types through validation, ranking, pair selection, and connectivity logic, and adding `Deref<Target=str>` for URL newtypes to reduce conversions. Side B fixes deployment and redirect behavior by centralizing base URL generation around `HOSTNAME`/`window.location.origin` and updating the staging deployment workflow, but its impact is narrower than A's architectural improvement that reduces future misuse of raw strings across many APIs.