feat(api): add AI text-to-deck generation, wallet deposit structure, and profile/notification endpoints

Fills the gaps between the admin panel screens and the backend: a full
free-text + slide-count + language -> AI-generated presentation flow with
new slide-cloning logic in TemplateFillService, a "my presentations" list
endpoint, a swappable payment-gateway structure for wallet top-ups (fake
driver for now), and avatar upload / public-profile toggle / account
deletion / password change / notification preference endpoints.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

app/Models/TemplateKey.php

@@ -15,6 +15,7 @@ use Illuminate\Database\Eloquent\Relations\BelongsTo;
     'type',
     'shape_name',
     'is_required',
+    'is_repeatable',
     'sort_order',
     'description',
 ])]
@@ -47,6 +48,7 @@ class TemplateKey extends Model
         return [
             'type' => TemplateKeyType::class,
             'is_required' => 'boolean',
+            'is_repeatable' => 'boolean',
             'sort_order' => 'integer',
         ];
     }