Replace the single-column-only feed with a max-columns model: one
Columns setting (1 / 2 / 3 / ∞) where 1 is the reading list and
anything wider packs into a Google-Keep-style column grid. There is
deliberately no separate list/grid mode — the setting is a ceiling,
and widths that only fit one column fall back to the flow list.
- ColumnGrid: absolute-positioned packing that only translates cards,
so appends and reorders never remount them; sticky column assignment
keeps existing cards in place when new memos arrive; tiles are capped
at 360px with a fade; columns clamp to 420px and center.
- Column one is the action column: the composer and active filters
stack as its first tile, and a just-created memo is pinned directly
beneath them.
- Multi-column always renders compact cards (policy centralized in
PagedMemoList and threaded through renderer(memo, { compact })).
- Setting persists in ViewContext localStorage; the settings menu
derives its options from the context's canonical value list.
