Send signed outgoing webhooks

Fed by the records themselves, delivered only to public HTTPS addresses
checked at every attempt, retried, and switched off after repeated failures.
A submitter's details travel only to webhooks that opted into them.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

tests/Feature/Api/AdminApiContractTest.php

@@ -22,6 +22,7 @@ use App\Models\Talk;
 use App\Models\Technology;
 use App\Models\Testimonial;
 use App\Models\User;
+use App\Models\Webhook;
 use App\Support\Maintenance;
 use Database\Seeders\RolePermissionSeeder;
 use Illuminate\Foundation\Testing\RefreshDatabase;
@@ -94,6 +95,7 @@ class AdminApiContractTest extends TestCase
             'repositories' => ['path' => '/v1/repositories'],
             'media' => ['path' => '/v1/media'],
             'tokens' => ['path' => '/v1/tokens'],
+            'webhooks' => ['path' => '/v1/webhooks'],
         ];
     }
 
@@ -118,6 +120,8 @@ class AdminApiContractTest extends TestCase
         $media = Media::factory()->create();
         $page->comment('Primera nota', $this->caller);
         ApiToken::issue($this->caller, 'CI', ['pages.*'], now()->addDay());
+        $webhook = Webhook::factory()->create(['is_active' => false]);
+        $webhook->deliveries()->create(['uuid' => 'contract', 'event' => 'ping', 'payload' => []]);
 
         // One request, one documented path — the URL a real caller hits and
         // the path key that describes it, side by side rather than derived
@@ -159,6 +163,9 @@ class AdminApiContractTest extends TestCase
             'medium' => ["/v1/media/{$media->id}", '/v1/media/{media}'],
             'revisions' => ["/v1/projects/{$project->id}/revisions", '/v1/projects/{project}/revisions'],
             'tokens' => ['/v1/tokens', '/v1/tokens'],
+            'webhooks' => ['/v1/webhooks', '/v1/webhooks'],
+            'webhook' => ["/v1/webhooks/{$webhook->id}", '/v1/webhooks/{webhook}'],
+            'deliveries' => ["/v1/webhooks/{$webhook->id}/deliveries", '/v1/webhooks/{webhook}/deliveries'],
             'review thread' => ["/v1/pages/{$page->id}/reviews", '/v1/pages/{page}/reviews'],
             'users' => ['/v1/users', '/v1/users'],
             'user' => ["/v1/users/{$this->caller->id}", '/v1/users/{user}'],