fix: page scrollbar width follows the scrollbar_width style knob

Was hardcoded 6px; now reads cce_ui::layout::scrollbar_width() like the
list scrollbars, so the config's style.control.scrollbar width drives
every bar in the app.

Co-Authored-By: Claude Fable 5 <[email protected]>

 src/renderer.rs | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/src/renderer.rs b/src/renderer.rs
index 1ce259f..c127f21 100644
--- a/src/renderer.rs
+++ b/src/renderer.rs
@@ -155,10 +155,11 @@ impl SystemInterface {
         // The page scrollbar (the only geometry the dissolved Page subtree ever emitted):
         // placed exactly as Page::layout did, updated with LAST frame's content height —
         // the legacy window pass also ran before this frame's content was measured.
+        let sb_w = cce_ui::layout::scrollbar_width();
         self.page_scroll_bar.set_rect(
-            self.sidebar_width + (logical_sw - self.sidebar_width) - 6.0 - 2.0,
+            self.sidebar_width + (logical_sw - self.sidebar_width) - sb_w - 2.0,
             self.header_height + 4.0,
-            6.0,
+            sb_w,
             switcher_h - 8.0,
         );
         if self.page_scroll_bar.dragging {