fix: keep admin section in place, don't move to top

Admin section stays in its fixed position (after Starred, before
Footer). Entering admin mode collapses Applications and Starred
but does not reorder sections.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

ui/src/components/LayoutShell.tsx

@@ -502,28 +502,6 @@ function LayoutContent() {
         title="Cameleer"
       />
 
-      {/* Admin section — shown at top when on admin pages */}
-      {isAdminPage && (
-        <Sidebar.Section
-          icon={createElement(Settings, { size: 16 })}
-          label="Admin"
-          open={adminOpen}
-          onToggle={toggleAdmin}
-          active
-        >
-          <SidebarTree
-            nodes={adminTreeNodes}
-            selectedPath={location.pathname}
-            isStarred={isStarred}
-            onToggleStar={toggleStar}
-            filterQuery={filterQuery}
-            persistKey="admin"
-            autoRevealPath={sidebarRevealPath}
-            onNavigate={handleSidebarNavigate}
-          />
-        </Sidebar.Section>
-      )}
-
       {/* Applications section */}
       <Sidebar.Section
         icon={createElement(Box, { size: 16 })}
@@ -559,16 +537,28 @@ function LayoutContent() {
         </Sidebar.Section>
       )}
 
-      {/* Footer — Admin + API Docs */}
+      {/* Admin section — stays in place, expands when on admin pages */}
+      <Sidebar.Section
+        icon={createElement(Settings, { size: 16 })}
+        label="Admin"
+        open={adminOpen}
+        onToggle={toggleAdmin}
+        active={isAdminPage}
+      >
+        <SidebarTree
+          nodes={adminTreeNodes}
+          selectedPath={location.pathname}
+          isStarred={isStarred}
+          onToggleStar={toggleStar}
+          filterQuery={filterQuery}
+          persistKey="admin"
+          autoRevealPath={sidebarRevealPath}
+          onNavigate={handleSidebarNavigate}
+        />
+      </Sidebar.Section>
+
+      {/* Footer */}
       <Sidebar.Footer>
-        {!isAdminPage && (
-          <Sidebar.FooterLink
-            icon={createElement(Settings, { size: 16 })}
-            label="Admin"
-            active={false}
-            onClick={() => navigate('/admin/rbac')}
-          />
-        )}
         <Sidebar.FooterLink
           icon={createElement(FileText, { size: 16 })}
           label="API Docs"