Added

• Resize pane splits by dragging the divider with the mouse (4px hit zone)

• Resize pane splits via Cmd+Option+Arrow keys (5% step per press)

• Mouse drag to reorder tabs in the tab bar (8px threshold to distinguish from click)

• Rename focused pane via context menu (Panes > Rename Pane) or command palette

• Double-click on pane header to rename (mirrors tab rename UX)

• Custom pane names persist across session save/restore