Scaffold @forte/admin package with React, Vite, shadcn/ui, TanStack Router

Sets up the admin frontend with login page, auth guard, API client, Zustand
auth store, and all shadcn/ui components. Vite proxies /v1 to backend in dev.

packages/admin/src/components/ui/skeleton.tsx

@@ -0,0 +1,13 @@
+import { cn } from "@/lib/utils"
+
+function Skeleton({ className, ...props }: React.ComponentProps<"div">) {
+  return (
+    <div
+      data-slot="skeleton"
+      className={cn("animate-pulse rounded-md bg-accent", className)}
+      {...props}
+    />
+  )
+}
+
+export { Skeleton }