feat: scaffold Vue 3 + TypeScript + Vite frontend admin panel

Set up web/ directory with complete frontend scaffolding:
- Vue 3 + TypeScript + Vite with Tailwind CSS v4
- Vue Router with auth guard (redirects to /login when unauthenticated)
- Pinia stores: auth, cookies, devices, settings
- Axios HTTP client with token interceptor
- Views: Login, Dashboard, Cookies, Devices, Settings
- Vite dev server proxy to relay API on port 8100
- Headless UI and Heroicons dependencies

Co-Authored-By: Paperclip <noreply@paperclip.ing>

web/env.d.ts

@@ -0,0 +1,11 @@
+/// <reference types="vite/client" />
+
+declare module "*.vue" {
+  import type { DefineComponent } from "vue";
+  const component: DefineComponent<
+    Record<string, unknown>,
+    Record<string, unknown>,
+    unknown
+  >;
+  export default component;
+}