- FilterBar: new Date pill hosts from/to inputs; calendar stays in left
sidebar (always visible, no collapse) with reduced padding and a
taller MONTH_HEIGHT so 6-week months render fully.
- LeftSidebar: drop Library collapse; Heaps regains its chevron toggle
to match Views/Folders.
- RightSidebar: render ActiveHeapCard above the Metadata header (with
its own eyebrow); preview overlay reuses RightSidebar so the active
heap stays visible there too.
- Toaster: top-right, more compact (smaller padding, font, gap).
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>