fix(call): strip-toggle icon no longer touches its frame edges

Shrink the StripToggleIcon SVG from 18x18 to 14x14 px so the 2-people
icon sits centred with ~11 px of breathing room inside its 36x36 button,
matching the h-4/w-4 small-icon convention used elsewhere in InCallPanel.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

apps/desktop/src/components/InCallPanel.tsx

@@ -1542,8 +1542,8 @@ function FullscreenCall({
 function StripToggleIcon({ hidden }: { hidden: boolean }) {
   return (
     <svg
-      width="18"
-      height="18"
+      width="14"
+      height="14"
       viewBox="0 0 24 24"
       fill="none"
       stroke="currentColor"