Remove the face carousel — one card presentation

03's resettlement reverses the pathfinder carry-over: the
selection-keyed dual presentation proved undesirable, so a card has one
presentation — selection changes styling, never geometry, and the
masonry never reflows on click. Deleted the carousel view (page dots,
glass underlay, scroll-tick monitor), the QuickLook thumbnail cache
(sole consumer), the pure paging/suppression rules, and the
sole-selected animation key — Motion now keys transactions on the
search query and the drop proposal only. The attachment chip stays as
the face's whole attachment story; viewing media is the card window's
job. No carousel state had leaked beyond the view layer.

Claude-Session: https://claude.ai/code/session_01SR4XGjmBE16ZUYWpfFHXwY

Kanban/UI/Board/MasonryLayout.swift

@@ -90,9 +90,9 @@ struct MasonryPlacement: Equatable, Sendable {
 /// Children are assigned round-robin to `columns` equal-width vertical columns (child `i` → column
 /// `i % columns`), and each column stacks its children top-aligned and independently — there is
 /// **no row alignment across columns**. With uniform card heights this renders exactly like a
-/// row-major grid, but when one card grows taller (the sole selected card's attachment carousel,
-/// 03-board-ui.md § Card face) it only pushes the cards below it in its *own* column; the
-/// neighbouring columns do not move.
+/// row-major grid, but when one card grows taller than its neighbours (a longer title wrapping
+/// across more lines, say) it only pushes the cards below it in its *own* column; the neighbouring
+/// columns do not move.
 ///
 /// A `Layout` rather than an `HStack` of per-column `VStack`s so the caller keeps a single
 /// `ForEach` — reflowing cards across columns preserves view identity and animates as positional