docs: redesign cards (#8671)

* docs: redesign cards

* fix build error

www/apps/book/app/not-found.mdx

@@ -22,26 +22,22 @@ If you think this is a mistake, please [report this issue on GitHub](https://git
     {
       title: "Get Started Docs",
       href: "/",
-      showLinkIcon: false,
-      startIcon: <BookOpen />
+      icon: BookOpen
     },
     {
       title: "Learning Resources",
       href: "!resources!",
-      showLinkIcon: false,
-      startIcon: <AcademicCapSolid />
+      icon: AcademicCapSolid
     },
     {
       title: "Admin API reference",
       href: "!api!/admin",
-      showLinkIcon: false,
-      startIcon: <ComputerDesktopSolid />
+      icon: ComputerDesktopSolid
     },
     {
       title: "Store API reference",
       href: "!api!/store",
-      showLinkIcon: false,
-      startIcon: <BuildingStorefront />
+      icon: BuildingStorefront
     }
   ]}
 />