fix: Shipping toggle refresh + AlertDialog + Local Pickup nav + Notifications info

## 1. Fixed Shipping Method Toggle State ✅
- Updated useEffect to properly sync selectedZone with zones data
- Added JSON comparison to prevent infinite loops
- Toggle now refreshes zone data correctly

## 2. Replace confirm() with AlertDialog ✅
- Added AlertDialog component for delete confirmation
- Shows method name in confirmation message
- Better UX with proper dialog styling
- Updated both desktop and mobile versions

## 3. Added Local Pickup to Navigation ✅
- Added "Local Pickup" menu item in Settings
- Now accessible from Settings > Local Pickup
- Path: /settings/local-pickup

## 4. Shipping Cost Shortcodes ✅
- Already supported via HTML rendering
- WooCommerce shortcodes like [fee percent="10"] work
- [qty], [cost] are handled by WooCommerce backend
- No additional SPA work needed

## 5. Enhanced Notifications Page ✅
- Added comprehensive info card explaining:
  - What WooNooW provides (simple toggle)
  - What WooCommerce provides (advanced config)
- Clear guidance on when to use each
- Links to WooCommerce for templates/styling
- Replaced ToggleField with Switch for simpler usage

## Key Decisions:
✅ AlertDialog > confirm() for better UX
✅ Notifications = Simple toggle + guidance to WC
✅ Shortcodes handled by WooCommerce (no SPA work)
✅ Local Pickup now discoverable in nav

admin-spa/src/nav/tree.ts

@@ -111,6 +111,7 @@ function getStaticFallbackTree(): MainNode[] {
         { label: 'Store Details', mode: 'spa' as const, path: '/settings/store' },
         { label: 'Payments', mode: 'spa' as const, path: '/settings/payments' },
         { label: 'Shipping & Delivery', mode: 'spa' as const, path: '/settings/shipping' },
+        { label: 'Local Pickup', mode: 'spa' as const, path: '/settings/local-pickup' },
         { label: 'Tax', mode: 'spa' as const, path: '/settings/tax' },
         { label: 'Checkout', mode: 'spa' as const, path: '/settings/checkout' },
         { label: 'Customer Accounts', mode: 'spa' as const, path: '/settings/customers' },