- Split Right / Split Down move from the bottom bar to the top bar as icon buttons (SplitRightIcon / SplitDownIcon) with hover tooltips, left of the workspace selector, shown only in tiling mode. Wired through the tiling handle (App.handleSplitRight/Down). - Title bar: compact fixed-height buttons (size-5) with header padding so hover highlights no longer reach the screen edge; tooltip + pointer cursor on the sidebar toggle, split buttons, and workspace menu. - Sidebar: fix asymmetric collapse animation — the open state now also transitions width, so re-opening animates instead of snapping. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>