feat: header mixed layout (#5263)

* feat: new layout header-mixed

* fix: header-mixed layout update

* feat: layout preference update

* fix: extra menus follow layout setting

packages/@core/ui-kit/layout-ui/src/hooks/use-layout.ts

@@ -31,9 +31,17 @@ export function useLayout(props: VbenLayoutProps) {
    */
   const isMixedNav = computed(() => currentLayout.value === 'mixed-nav');
 
+  /**
+   * 是否为头部混合模式
+   */
+  const isHeaderMixedNav = computed(
+    () => currentLayout.value === 'header-mixed-nav',
+  );
+
   return {
     currentLayout,
     isFullContent,
+    isHeaderMixedNav,
     isHeaderNav,
     isMixedNav,
     isSidebarMixedNav,