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/button.tsx

@@ -0,0 +1,65 @@
+import * as React from "react"
+import { cva, type VariantProps } from "class-variance-authority"
+import { Slot } from "radix-ui"
+
+import { cn } from "@/lib/utils"
+
+const buttonVariants = cva(
+  "group/button inline-flex shrink-0 items-center justify-center rounded-md border border-transparent bg-clip-padding text-xs/relaxed font-medium whitespace-nowrap transition-all outline-none select-none focus-visible:border-ring focus-visible:ring-2 focus-visible:ring-ring/30 active:translate-y-px disabled:pointer-events-none disabled:opacity-50 aria-invalid:border-destructive aria-invalid:ring-2 aria-invalid:ring-destructive/20 dark:aria-invalid:border-destructive/50 dark:aria-invalid:ring-destructive/40 [&_svg]:pointer-events-none [&_svg]:shrink-0 [&_svg:not([class*='size-'])]:size-4",
+  {
+    variants: {
+      variant: {
+        default: "bg-primary text-primary-foreground hover:bg-primary/80",
+        outline:
+          "border-border hover:bg-input/50 hover:text-foreground aria-expanded:bg-muted aria-expanded:text-foreground dark:bg-input/30",
+        secondary:
+          "bg-secondary text-secondary-foreground hover:bg-secondary/80 aria-expanded:bg-secondary aria-expanded:text-secondary-foreground",
+        ghost:
+          "hover:bg-muted hover:text-foreground aria-expanded:bg-muted aria-expanded:text-foreground dark:hover:bg-muted/50",
+        destructive:
+          "bg-destructive/10 text-destructive hover:bg-destructive/20 focus-visible:border-destructive/40 focus-visible:ring-destructive/20 dark:bg-destructive/20 dark:hover:bg-destructive/30 dark:focus-visible:ring-destructive/40",
+        link: "text-primary underline-offset-4 hover:underline",
+      },
+      size: {
+        default:
+          "h-7 gap-1 px-2 text-xs/relaxed has-data-[icon=inline-end]:pr-1.5 has-data-[icon=inline-start]:pl-1.5 [&_svg:not([class*='size-'])]:size-3.5",
+        xs: "h-5 gap-1 rounded-sm px-2 text-[0.625rem] has-data-[icon=inline-end]:pr-1.5 has-data-[icon=inline-start]:pl-1.5 [&_svg:not([class*='size-'])]:size-2.5",
+        sm: "h-6 gap-1 px-2 text-xs/relaxed has-data-[icon=inline-end]:pr-1.5 has-data-[icon=inline-start]:pl-1.5 [&_svg:not([class*='size-'])]:size-3",
+        lg: "h-8 gap-1 px-2.5 text-xs/relaxed has-data-[icon=inline-end]:pr-2 has-data-[icon=inline-start]:pl-2 [&_svg:not([class*='size-'])]:size-4",
+        icon: "size-7 [&_svg:not([class*='size-'])]:size-3.5",
+        "icon-xs": "size-5 rounded-sm [&_svg:not([class*='size-'])]:size-2.5",
+        "icon-sm": "size-6 [&_svg:not([class*='size-'])]:size-3",
+        "icon-lg": "size-8 [&_svg:not([class*='size-'])]:size-4",
+      },
+    },
+    defaultVariants: {
+      variant: "default",
+      size: "default",
+    },
+  }
+)
+
+function Button({
+  className,
+  variant = "default",
+  size = "default",
+  asChild = false,
+  ...props
+}: React.ComponentProps<"button"> &
+  VariantProps<typeof buttonVariants> & {
+    asChild?: boolean
+  }) {
+  const Comp = asChild ? Slot.Root : "button"
+
+  return (
+    <Comp
+      data-slot="button"
+      data-variant={variant}
+      data-size={size}
+      className={cn(buttonVariants({ variant, size, className }))}
+      {...props}
+    />
+  )
+}
+
+export { Button, buttonVariants }