Add urapt-web: web UI for urapt-server instances

A Vite + React 18 + TypeScript SPA, same-origin with the API (no CORS,
no Go server changes). Full management parity with the urapt CLI:

- First-run setup (admin bootstrap via needs_setup), login/logout
- Repositories: list, create, tabbed detail (overview edit/delete,
  members CRUD, distributions/components/architectures manager,
  package list + .deb upload + detail + delete, apt-config panel)
- API tokens: show-once creation + revoke
- Admin users: toggle admin / delete
- Settings + dark mode

Stack: Tailwind + shadcn/ui (New York), React Router v7 (lazy routes),
TanStack Query v5, Zustand, Vitest. Hand-written typed API client
mirroring shared/api + shared/models. Dev proxy forwards /api + /apt
to a local urapt-server; deploy behind nginx/Caddy (see urapt-web/README).

urapt-web/src/components/ui/card.tsx

@@ -0,0 +1,61 @@
+import * as React from "react";
+
+import { cn } from "@/lib/utils";
+
+const Card = React.forwardRef<HTMLDivElement, React.HTMLAttributes<HTMLDivElement>>(
+  ({ className, ...props }, ref) => (
+    <div
+      ref={ref}
+      className={cn("rounded-xl border bg-card text-card-foreground shadow", className)}
+      {...props}
+    />
+  ),
+);
+Card.displayName = "Card";
+
+const CardHeader = React.forwardRef<HTMLDivElement, React.HTMLAttributes<HTMLDivElement>>(
+  ({ className, ...props }, ref) => (
+    <div
+      ref={ref}
+      className={cn("flex flex-col space-y-1.5 p-6", className)}
+      {...props}
+    />
+  ),
+);
+CardHeader.displayName = "CardHeader";
+
+const CardTitle = React.forwardRef<HTMLDivElement, React.HTMLAttributes<HTMLDivElement>>(
+  ({ className, ...props }, ref) => (
+    <div
+      ref={ref}
+      className={cn("font-semibold leading-none tracking-tight", className)}
+      {...props}
+    />
+  ),
+);
+CardTitle.displayName = "CardTitle";
+
+const CardDescription = React.forwardRef<
+  HTMLDivElement,
+  React.HTMLAttributes<HTMLDivElement>
+>(({ className, ...props }, ref) => (
+  <div ref={ref} className={cn("text-sm text-muted-foreground", className)} {...props} />
+));
+CardDescription.displayName = "CardDescription";
+
+const CardContent = React.forwardRef<
+  HTMLDivElement,
+  React.HTMLAttributes<HTMLDivElement>
+>(({ className, ...props }, ref) => (
+  <div ref={ref} className={cn("p-6 pt-0", className)} {...props} />
+));
+CardContent.displayName = "CardContent";
+
+const CardFooter = React.forwardRef<HTMLDivElement, React.HTMLAttributes<HTMLDivElement>>(
+  ({ className, ...props }, ref) => (
+    <div ref={ref} className={cn("flex items-center p-6 pt-0", className)} {...props} />
+  ),
+);
+CardFooter.displayName = "CardFooter";
+
+export { Card, CardHeader, CardFooter, CardTitle, CardDescription, CardContent };