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/components/ui/switch.tsx

@@ -0,0 +1,33 @@
+"use client"
+
+import * as React from "react"
+import { Switch as SwitchPrimitive } from "radix-ui"
+
+import { cn } from "@/lib/utils"
+
+function Switch({
+  className,
+  size = "default",
+  ...props
+}: React.ComponentProps<typeof SwitchPrimitive.Root> & {
+  size?: "sm" | "default"
+}) {
+  return (
+    <SwitchPrimitive.Root
+      data-slot="switch"
+      data-size={size}
+      className={cn(
+        "peer group/switch relative inline-flex shrink-0 items-center rounded-full border border-transparent transition-all outline-none after:absolute after:-inset-x-3 after:-inset-y-2 focus-visible:border-ring focus-visible:ring-2 focus-visible:ring-ring/30 aria-invalid:border-destructive aria-invalid:ring-2 aria-invalid:ring-destructive/20 data-[size=default]:h-[16.6px] data-[size=default]:w-[28px] data-[size=sm]:h-[14px] data-[size=sm]:w-[24px] dark:aria-invalid:border-destructive/50 dark:aria-invalid:ring-destructive/40 data-checked:bg-primary data-unchecked:bg-input dark:data-unchecked:bg-input/80 data-disabled:cursor-not-allowed data-disabled:opacity-50",
+        className
+      )}
+      {...props}
+    >
+      <SwitchPrimitive.Thumb
+        data-slot="switch-thumb"
+        className="pointer-events-none block rounded-full bg-background ring-0 transition-transform group-data-[size=default]/switch:size-3.5 group-data-[size=sm]/switch:size-3 group-data-[size=default]/switch:data-checked:translate-x-[calc(100%-2px)] group-data-[size=sm]/switch:data-checked:translate-x-[calc(100%-2px)] dark:data-checked:bg-primary-foreground group-data-[size=default]/switch:data-unchecked:translate-x-0 group-data-[size=sm]/switch:data-unchecked:translate-x-0 dark:data-unchecked:bg-foreground"
+      />
+    </SwitchPrimitive.Root>
+  )
+}
+
+export { Switch }