fix(icons): use configure.svg (Win11 gear) for System Settings app icon

preferences-system is the icon name used by systemsettings.desktop.
Previous SVG had the right gear shape but wrong colors; configure.svg
is the correct Windows 11 Settings gear with proper gradient.

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

Author: TuxLux40

icons/win11-kde/apps/scalable/preferences-system.svg

@@ -0,0 +1 @@
+configure.svg