openai/gpt-chat-latest → A (4:1)

Side A fixes a real functional bug where the external garden index (`/-/`) appeared empty by introducing `external_root_host_items`, and it also adds a durable resolver architecture (`server/src/resolvers/`) with GitHub import-card storage/rendering, integration into item rendering, and accompanying tests. Side B is a valuable correctness fix—removing browser sentinel delegates so browser users no longer share a delegate and multi-user voting works correctly—but it is a narrower authentication/data-model change centered on making browser sessions use `None` delegates and updating attribution and tests.