Add audit trail: AuditLog entity, AuditService, admin logs page

- AuditLog entity: action, entityType, entityId, data (JSON), performedBy, ipAddress
- AuditService: logs actions with current user and IP
- Audit on: order_created, order_paid, order_cancelled, order_refunded
- Admin /admin/logs: paginated table with action badges, details, user, IP
- Navigation link 'Logs' in admin header

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

phpstan.neon

@@ -6,7 +6,7 @@ parameters:
         - src/Kernel.php
     ignoreErrors:
         -
-            message: '#Property App\\Entity\\(EmailTracking|MessengerLog|User|Payout|Event|Category|Billet|BilletDesign|BilletBuyer|BilletBuyerItem|BilletOrder|OrganizerInvitation)::\$id .* never assigned#'
+            message: '#Property App\\Entity\\(EmailTracking|MessengerLog|User|Payout|Event|Category|Billet|BilletDesign|BilletBuyer|BilletBuyerItem|BilletOrder|OrganizerInvitation|AuditLog)::\$id .* never assigned#'
             reportUnmatched: false
             paths:
                 - src/Entity/EmailTracking.php
@@ -21,6 +21,7 @@ parameters:
                 - src/Entity/BilletBuyerItem.php
                 - src/Entity/BilletOrder.php
                 - src/Entity/OrganizerInvitation.php
+                - src/Entity/AuditLog.php
         -
             message: '#Parameter \#1 \$params of method Stripe\\Service\\.*::create\(\) expects#'
             path: src/Controller/OrderController.php