feat: add WebhookChannel placeholder implementation

Add basic WebhookChannel infrastructure:
- Create SendsWebhook interface
- Create WebhookChannel with placeholder implementation (logs instead of sending)
- Update Test notification to support webhook channel
- Add WebhookChannel to HasNotificationSettings trait
- Add toWebhook() method to Test notification

This provides a working foundation that won't break test notifications.
The actual HTTP webhook delivery will be implemented in a follow-up.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

app/Notifications/Channels/SendsWebhook.php

@@ -0,0 +1,8 @@
+<?php
+
+namespace App\Notifications\Channels;
+
+interface SendsWebhook
+{
+    public function routeNotificationForWebhook();
+}

app/Notifications/Channels/WebhookChannel.php

@@ -0,0 +1,33 @@
+<?php
+
+namespace App\Notifications\Channels;
+
+use Illuminate\Notifications\Notification;
+use Illuminate\Support\Facades\Log;
+
+class WebhookChannel
+{
+    /**
+     * Send the given notification.
+     */
+    public function send(SendsWebhook $notifiable, Notification $notification): void
+    {
+        $webhookSettings = $notifiable->webhookNotificationSettings;
+
+        if (! $webhookSettings || ! $webhookSettings->isEnabled() || ! $webhookSettings->webhook_url) {
+            return;
+        }
+
+        // TODO: Implement actual webhook delivery
+        // This is a placeholder implementation
+        // You'll need to:
+        // 1. Get the webhook payload from $notification->toWebhook()
+        // 2. Create a job to send the HTTP POST request to $webhookSettings->webhook_url
+        // 3. Handle retries and errors appropriately
+
+        Log::info('Webhook notification would be sent', [
+            'url' => $webhookSettings->webhook_url,
+            'notification' => get_class($notification),
+        ]);
+    }
+}

app/Notifications/Test.php

@@ -7,6 +7,7 @@
 use App\Notifications\Channels\PushoverChannel;
 use App\Notifications\Channels\SlackChannel;
 use App\Notifications\Channels\TelegramChannel;
+use App\Notifications\Channels\WebhookChannel;
 use App\Notifications\Dto\DiscordMessage;
 use App\Notifications\Dto\PushoverMessage;
 use App\Notifications\Dto\SlackMessage;
@@ -36,7 +37,7 @@ public function via(object $notifiable): array
                 'telegram' => [TelegramChannel::class],
                 'slack' => [SlackChannel::class],
                 'pushover' => [PushoverChannel::class],
-                'webhook' => [], // WebhookChannel will be implemented later
+                'webhook' => [WebhookChannel::class],
                 default => [],
             };
         } else {
@@ -111,4 +112,13 @@ public function toSlack(): SlackMessage
             description: 'This is a test Slack notification from Coolify.'
         );
     }
+
+    public function toWebhook(): array
+    {
+        return [
+            'event' => 'test',
+            'message' => 'This is a test webhook notification from Coolify.',
+            'url' => base_url(),
+        ];
+    }
 }

app/Traits/HasNotificationSettings.php

@@ -7,6 +7,7 @@
 use App\Notifications\Channels\PushoverChannel;
 use App\Notifications\Channels\SlackChannel;
 use App\Notifications\Channels\TelegramChannel;
+use App\Notifications\Channels\WebhookChannel;
 use Illuminate\Database\Eloquent\Model;
 
 trait HasNotificationSettings
@@ -78,6 +79,7 @@ public function getEnabledChannels(string $event): array
             'telegram' => TelegramChannel::class,
             'slack' => SlackChannel::class,
             'pushover' => PushoverChannel::class,
+            'webhook' => WebhookChannel::class,
         ];
 
         if ($event === 'general') {