fix(sw): even out the multi step header tool group margins without window buttons

With appearance="multi" and all window controls hidden, the tool group is the last
child of the window area; give it the same 5px right margin as its left margin.
The existing 2px margin stays whenever a window button follows. default and other
headers are unchanged.

packages/sw/src/theme/sw-process-header.css

@@ -498,6 +498,9 @@
 }
 /* SW pill at the Figma place: 41 high, 4 from the top, 5 from the window start, 2 before the window move. */
 .hm-sw-process-header[data-appearance="multi"] .hm-sw-process-header__window .hm-sw-process-header__tools { height: 41px; margin: 4px 2px 0 5px; }
+/* No window button follows the pill (window move, minimize, maximize, close all hidden; the pill is then the last child of the
+   window area): the 2px gap to the window move is not needed, so the pill gets the same 5px at both ends. */
+.hm-sw-process-header[data-appearance="multi"] .hm-sw-process-header__window .hm-sw-process-header__tools:last-child { margin-right: 5px; }
 .hm-sw-process-header[data-appearance="multi"] .hm-sw-process-header__tools .hm-sw-tool__pill-button { height: 37px; }
 
 /* Lit middle group (neither the first nor the last; Figma 6797:16225): the two start_bg overlay layers (0.85 / 0.45, lit-group