feat: add admin dashboard app (#91)

* feat: add admin dashboard app

- React + Vite + TanStack Router + TanStack Query
- Auth with better-auth (login, session, admin guard)
- Source config management (WeatherKit credentials, user config)
- Feed query panel
- Location push card
- General settings with health check
- CORS middleware for cross-origin auth
- Disable CSRF check in dev mode
- Sonner toasts for mutation feedback

Co-authored-by: Ona <no-reply@ona.com>

* fix: use useQuery instead of getQueryData

Co-authored-by: Ona <no-reply@ona.com>

* refactor: remove backend changes from dashboard PR

Backend CORS/CSRF changes moved to #92.
Source registry removed (sources hardcoded in frontend).

Co-authored-by: Ona <no-reply@ona.com>

---------

Co-authored-by: Ona <no-reply@ona.com>

apps/admin-dashboard/src/main.tsx

@@ -0,0 +1,28 @@
+import { QueryClient, QueryClientProvider } from "@tanstack/react-query"
+import { StrictMode } from "react"
+import { createRoot } from "react-dom/client"
+
+import "./index.css"
+import App from "./App.tsx"
+import { ThemeProvider } from "@/components/theme-provider.tsx"
+import { Toaster } from "@/components/ui/sonner.tsx"
+
+const queryClient = new QueryClient({
+  defaultOptions: {
+    queries: {
+      retry: false,
+      refetchOnWindowFocus: false,
+    },
+  },
+})
+
+createRoot(document.getElementById("root")!).render(
+  <StrictMode>
+    <QueryClientProvider client={queryClient}>
+      <ThemeProvider>
+        <App />
+        <Toaster />
+      </ThemeProvider>
+    </QueryClientProvider>
+  </StrictMode>
+)