Redesign card 6d5a97fd resolved off the 2026-08-01 live try-out: leading is board identity, center is view controls, trailing stays the user's catalog. centeredItemIdentifiers, not a flexible-space sandwich — centers against the window, holds as catalog items install, reaches machines with a saved arrangement; defaultItems and its pinned tests untouched. 03 records the grammar and the accepted tensions (widget-vs-field budget in narrow windows, HIG's trailing convention yielding). Claude-Session: https://claude.ai/code/session_014PtZdPwqZuqEDLc6wZMtEy