Add cardGridLayout helpers, useCardGridMetrics, useRemeasureGridVirtualizer, and VirtualCardGrid (TanStack row virtualization, always remeasure on layout changes).
Apply to Artists (grid + list unchanged policy), Albums, Composers grid, playlists, radio stations, offline library, and album-heavy browse/detail pages. Respect disableMainstageVirtualLists for a non-virtual grid with the same column rules.
Includes vitest coverage for column cap.
Maxim Isaev