- SidebarResizer: pointer-drag handle on the sidebar's right edge,
keyboard-adjustable (arrows, Home/End), double-click resets to the
16rem default; width clamped to 12-32rem
- AppLayout persists the width via usePersistentState (ui.sidebar.width)
and sets --sidebar-width inline on .app-body, so collapse/force-hide
keep animating from/to the chosen width
- localized aria-label (de+en), handle hidden while collapsed
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01EwZ4jR4KFAPvpjWevfUGX1
