Polish round: node-delete chrome + rename alignment

Owner polish dispatch (2026-09-23):

- Right-click no longer pins a node or opens the detail card: the
  canvas pointerdown/up handlers now gate on the primary button, so
  the context menu arrives alone.
- Node context menu: label is just "Delete" and the shell hugs its
  content (w-44 -> w-fit); the menu body keeps focus for arrow
  cycling but never shows the browser's default focus ring
  (outline-none on the MenuShell body - applies to every menu).
- Delete confirm: "Delete node?" title in CMU Serif, red
  (text-destructive); the node name sits below in JetBrains Mono
  inline-code; the Delete button carries the destructive treatment
  (border + tint, fill deepens on hover). Rest of the dialog stays
  neutral.
- Sidebar rename row: text and metadata stay at the idle row's x -
  the status spacer and the input's border/padding are gone; the
  underline is the only editing cue.

components/menu-shell.tsx

@@ -246,7 +246,12 @@ export function MenuShell({
 			tabIndex={-1}
 			onKeyDown={onBodyKeyDown}
 			style={{ position: "fixed", zIndex: 60, ...placed.style, maxHeight: placed.maxHeight, overflowY: "auto" }}
-			className={menuClass}
+			// The body is the arrow machine's focus home (input-less menus
+			// land focus here on open) — the focus STAYS, but the browser's
+			// default blue ring around it must not draw (owner, polish
+			// round). Arrow cycling moves DOM focus to the buttons, which
+			// carry their own hover/highlight; the ring is pure noise.
+			className={`${menuClass} outline-none`}
 		>
 			{children}
 		</div>,