only the access-wall decision does (the composer shows a loader until the broker answers), and the node's HTML starts the broker iframe itself so the sibling app boots in parallel with our bundle instead of after it (the client adopts the frame by id) Claude-Session: https://claude.ai/code/session_014aPQ5yqG9QFxKnbwQfCYKa (cherry picked from commit 8783803a3db4502a2487d7a532bd7914d93da0a3)