feat: Implement push notification settings backend and UI

## ✅ Push Notification Settings - Fully Functional

### Backend (PHP)

**PushNotificationHandler Updates:**
- Added `SETTINGS_KEY` constant
- `ensure_default_settings()` - Initialize defaults
- `get_default_settings()` - Return default config
- `get_settings()` - Fetch current settings
- `update_settings()` - Save settings

**Default Settings:**
```php
[
  'use_logo' => true,
  'use_product_images' => true,
  'use_gravatar' => false,
  'click_action' => '/wp-admin/admin.php?page=woonoow#/orders',
  'require_interaction' => false,
  'silent' => false,
]
```

**NotificationsController:**
- `GET /notifications/push/settings` - Fetch settings
- `POST /notifications/push/settings` - Update settings
- Permission-protected endpoints

### Frontend (React)

**ChannelConfig Component:**
- Fetches push settings on open
- Real-time state management
- Connected switches and inputs
- Save mutation with loading state
- Toast notifications for success/error
- Disabled state during save

**Settings Available:**
1. **Branding**
   - Use Store Logo
   - Use Product Images
   - Use Customer Gravatar

2. **Behavior**
   - Click Action URL (input)
   - Require Interaction
   - Silent Notifications

### Features

✅ **Backend Storage** - Settings saved in wp_options
✅ **REST API** - GET and POST endpoints
✅ **Frontend UI** - Full CRUD interface
✅ **State Management** - React Query integration
✅ **Loading States** - Skeleton and button states
✅ **Error Handling** - Toast notifications
✅ **Default Values** - Sensible defaults

---

**Next: Email channel toggle** 📧

admin-spa/src/routes/Settings/Notifications/ChannelConfig.tsx

@@ -1,4 +1,6 @@
-import React from 'react';
+import React, { useState, useEffect } from 'react';
+import { useQuery, useMutation, useQueryClient } from '@tanstack/react-query';
+import { api } from '@/lib/api';
 import {
   Dialog,
   DialogContent,
@@ -10,7 +12,8 @@ import { Button } from '@/components/ui/button';
 import { Label } from '@/components/ui/label';
 import { Input } from '@/components/ui/input';
 import { Switch } from '@/components/ui/switch';
-import { ExternalLink } from 'lucide-react';
+import { ExternalLink, Loader2 } from 'lucide-react';
+import { toast } from 'sonner';
 import { __ } from '@/lib/i18n';
 
 interface ChannelConfigProps {
@@ -71,6 +74,45 @@ export default function ChannelConfig({ open, onClose, channelId, channelLabel }
 
   // Push notification configuration
   if (channelId === 'push') {
+    const queryClient = useQueryClient();
+    const [settings, setSettings] = useState({
+      use_logo: true,
+      use_product_images: true,
+      use_gravatar: false,
+      click_action: '/wp-admin/admin.php?page=woonoow#/orders',
+      require_interaction: false,
+      silent: false,
+    });
+
+    // Fetch push settings
+    const { data: pushSettings, isLoading } = useQuery({
+      queryKey: ['push-settings'],
+      queryFn: () => api.get('/notifications/push/settings'),
+      enabled: open,
+    });
+
+    // Update local state when data is fetched
+    useEffect(() => {
+      if (pushSettings) {
+        setSettings(pushSettings);
+      }
+    }, [pushSettings]);
+
+    // Save settings mutation
+    const saveMutation = useMutation({
+      mutationFn: async () => {
+        return api.post('/notifications/push/settings', settings);
+      },
+      onSuccess: () => {
+        queryClient.invalidateQueries({ queryKey: ['push-settings'] });
+        toast.success(__('Push notification settings saved'));
+        onClose();
+      },
+      onError: (error: any) => {
+        toast.error(error?.message || __('Failed to save settings'));
+      },
+    });
+
     return (
       <Dialog open={open} onOpenChange={onClose}>
         <DialogContent>
@@ -81,6 +123,11 @@ export default function ChannelConfig({ open, onClose, channelId, channelLabel }
             </DialogDescription>
           </DialogHeader>
 
+          {isLoading ? (
+            <div className="flex items-center justify-center py-8">
+              <Loader2 className="h-6 w-6 animate-spin text-muted-foreground" />
+            </div>
+          ) : (
             <div className="space-y-6 py-4">
             {/* Branding */}
             <div className="space-y-3">
@@ -93,7 +140,11 @@ export default function ChannelConfig({ open, onClose, channelId, channelLabel }
                       {__('Display your store logo in push notifications')}
                     </p>
                   </div>
-                  <Switch id="use-logo" defaultChecked />
+                  <Switch 
+                    id="use-logo" 
+                    checked={settings.use_logo}
+                    onCheckedChange={(checked) => setSettings({...settings, use_logo: checked})}
+                  />
                 </div>
 
                 <div className="flex items-center justify-between">
@@ -103,7 +154,11 @@ export default function ChannelConfig({ open, onClose, channelId, channelLabel }
                       {__('Show product images in order notifications')}
                     </p>
                   </div>
-                  <Switch id="use-product-image" defaultChecked />
+                  <Switch 
+                    id="use-product-image" 
+                    checked={settings.use_product_images}
+                    onCheckedChange={(checked) => setSettings({...settings, use_product_images: checked})}
+                  />
                 </div>
 
                 <div className="flex items-center justify-between">
@@ -113,7 +168,11 @@ export default function ChannelConfig({ open, onClose, channelId, channelLabel }
                       {__('Display customer avatar when available')}
                     </p>
                   </div>
-                  <Switch id="use-gravatar" />
+                  <Switch 
+                    id="use-gravatar" 
+                    checked={settings.use_gravatar}
+                    onCheckedChange={(checked) => setSettings({...settings, use_gravatar: checked})}
+                  />
                 </div>
               </div>
             </div>
@@ -127,7 +186,8 @@ export default function ChannelConfig({ open, onClose, channelId, channelLabel }
                   <Input
                     id="click-action"
                     placeholder={__('https://yourstore.com/orders')}
-                    defaultValue="/wp-admin/admin.php?page=woonoow#/orders"
+                    value={settings.click_action}
+                    onChange={(e) => setSettings({...settings, click_action: e.target.value})}
                   />
                   <p className="text-xs text-muted-foreground">
                     {__('Where users are redirected when clicking the notification')}
@@ -141,7 +201,11 @@ export default function ChannelConfig({ open, onClose, channelId, channelLabel }
                       {__('Notification stays until user dismisses it')}
                     </p>
                   </div>
-                  <Switch id="require-interaction" />
+                  <Switch 
+                    id="require-interaction" 
+                    checked={settings.require_interaction}
+                    onCheckedChange={(checked) => setSettings({...settings, require_interaction: checked})}
+                  />
                 </div>
 
                 <div className="flex items-center justify-between">
@@ -151,7 +215,11 @@ export default function ChannelConfig({ open, onClose, channelId, channelLabel }
                       {__('Disable notification sound')}
                     </p>
                   </div>
-                  <Switch id="silent" />
+                  <Switch 
+                    id="silent" 
+                    checked={settings.silent}
+                    onCheckedChange={(checked) => setSettings({...settings, silent: checked})}
+                  />
                 </div>
               </div>
             </div>
@@ -162,13 +230,22 @@ export default function ChannelConfig({ open, onClose, channelId, channelLabel }
               </p>
             </div>
             </div>
+          )
+          }
 
           <div className="flex justify-end gap-2">
-            <Button variant="outline" onClick={onClose}>
+            <Button variant="outline" onClick={onClose} disabled={saveMutation.isPending}>
               {__('Cancel')}
             </Button>
-            <Button onClick={onClose}>
+            <Button onClick={() => saveMutation.mutate()} disabled={saveMutation.isPending || isLoading}>
-              {__('Save Configuration')}
+              {saveMutation.isPending ? (
+                <>
+                  <Loader2 className="h-4 w-4 mr-2 animate-spin" />
+                  {__('Saving...')}
+                </>
+              ) : (
+                __('Save Configuration')
+              )}
             </Button>
           </div>
         </DialogContent>

includes/Api/NotificationsController.php

@@ -120,6 +120,24 @@ class NotificationsController {
 				'permission_callback' => '__return_true',
 			],
 		]);
+		
+		// GET /woonoow/v1/notifications/push/settings
+		register_rest_route($this->namespace, '/' . $this->rest_base . '/push/settings', [
+			[
+				'methods' => 'GET',
+				'callback' => [$this, 'get_push_settings'],
+				'permission_callback' => [$this, 'check_permission'],
+			],
+		]);
+		
+		// POST /woonoow/v1/notifications/push/settings
+		register_rest_route($this->namespace, '/' . $this->rest_base . '/push/settings', [
+			[
+				'methods' => 'POST',
+				'callback' => [$this, 'update_push_settings'],
+				'permission_callback' => [$this, 'check_permission'],
+			],
+		]);
 	}
 	
 	/**
@@ -468,4 +486,50 @@ class NotificationsController {
 			'message' => __('Unsubscribed from push notifications', 'woonoow'),
 		], 200);
 	}
+	
+	/**
+	 * Get push notification settings
+	 * 
+	 * @param WP_REST_Request $request Request object
+	 * @return WP_REST_Response
+	 */
+	public function get_push_settings(WP_REST_Request $request) {
+		$settings = PushNotificationHandler::get_settings();
+		
+		return new WP_REST_Response($settings, 200);
+	}
+	
+	/**
+	 * Update push notification settings
+	 * 
+	 * @param WP_REST_Request $request Request object
+	 * @return WP_REST_Response
+	 */
+	public function update_push_settings(WP_REST_Request $request) {
+		$settings = $request->get_json_params();
+		
+		if (empty($settings)) {
+			return new WP_Error(
+				'invalid_settings',
+				__('Settings data is required', 'woonoow'),
+				['status' => 400]
+			);
+		}
+		
+		$success = PushNotificationHandler::update_settings($settings);
+		
+		if (!$success) {
+			return new WP_Error(
+				'update_failed',
+				__('Failed to update push notification settings', 'woonoow'),
+				['status' => 500]
+			);
+		}
+		
+		return new WP_REST_Response([
+			'success' => true,
+			'message' => __('Push notification settings updated', 'woonoow'),
+			'settings' => PushNotificationHandler::get_settings(),
+		], 200);
+	}
 }

includes/Core/Notifications/PushNotificationHandler.php

@@ -21,12 +21,80 @@ class PushNotificationHandler {
 	 */
 	const VAPID_KEYS_KEY = 'woonoow_push_vapid_keys';
 	
+	/**
+	 * Option key for push settings
+	 */
+	const SETTINGS_KEY = 'woonoow_push_settings';
+	
 	/**
 	 * Initialize push notifications
 	 */
 	public static function init() {
 		// Generate VAPID keys if not exists
 		self::ensure_vapid_keys();
+		
+		// Ensure default settings exist
+		self::ensure_default_settings();
+	}
+	
+	/**
+	 * Ensure default push settings exist
+	 * 
+	 * @return array
+	 */
+	public static function ensure_default_settings() {
+		$settings = get_option(self::SETTINGS_KEY);
+		
+		if (!$settings) {
+			$settings = self::get_default_settings();
+			update_option(self::SETTINGS_KEY, $settings);
+		}
+		
+		return $settings;
+	}
+	
+	/**
+	 * Get default push settings
+	 * 
+	 * @return array
+	 */
+	public static function get_default_settings() {
+		return [
+			'use_logo' => true,
+			'use_product_images' => true,
+			'use_gravatar' => false,
+			'click_action' => '/wp-admin/admin.php?page=woonoow#/orders',
+			'require_interaction' => false,
+			'silent' => false,
+		];
+	}
+	
+	/**
+	 * Get push settings
+	 * 
+	 * @return array
+	 */
+	public static function get_settings() {
+		$settings = get_option(self::SETTINGS_KEY);
+		
+		if (!$settings) {
+			$settings = self::get_default_settings();
+		}
+		
+		return $settings;
+	}
+	
+	/**
+	 * Update push settings
+	 * 
+	 * @param array $settings
+	 * @return bool
+	 */
+	public static function update_settings($settings) {
+		$current = self::get_settings();
+		$updated = array_merge($current, $settings);
+		
+		return update_option(self::SETTINGS_KEY, $updated);
 	}
 	
 	/**