feat(ui): [UI7-1] 构建通用原子UI组件与业务Hooks

client/src/components/ui/skeleton.tsx

@@ -0,0 +1,5 @@
+import { cn } from "../../lib/utils";
+
+export function Skeleton({ className, ...props }: React.HTMLAttributes<HTMLDivElement>) {
+  return <div className={cn("animate-pulse rounded-md bg-slate-200", className)} {...props} />;
+}