fix: center sidebar footer divider and correct Apps arrow

Use equal-width Apps and Settings buttons so the divider stays centered. Increase divider visibility and point the Apps arrow upward to match the menu opening direction.

Release note: Make the sidebar footer divider clearer and centered, and align the Apps arrow with its upward-opening menu.

src/renderer/src/App.tsx

@@ -31,6 +31,7 @@ import {
   Check,
   CheckCircle2,
   ChevronDown,
+  ChevronUp,
   ChevronRight,
   CircleAlert,
   CircleHelp,
@@ -9350,7 +9351,7 @@ function App(): React.JSX.Element {
           >
             <Grid2X2 size={17} aria-hidden="true" />
             <span>{t("applications.menuLabel")}</span>
-            <ChevronDown size={16} aria-hidden="true" />
+            <ChevronUp size={16} aria-hidden="true" />
           </button>
           <div className="sidebar-footer__divider" aria-hidden="true" />
           <button

src/renderer/src/application-center.css

@@ -205,7 +205,8 @@
   gap: var(--space-2);
 }
 .sidebar-footer--applications > .nav-item {
-  flex: 1 0 auto;
+  flex: 1 1 0;
+  min-width: 0;
   gap: var(--space-2);
   padding-inline: var(--space-2);
   justify-content: center;
@@ -216,6 +217,6 @@
 }
 .sidebar-footer__divider {
   flex: 0 0 1px;
-  height: var(--space-4);
-  background: var(--border-subtle);
+  height: var(--space-6);
+  background: var(--border-control);
 }