Add feature to mark orders as completed

Implemented a new endpoint to mark orders as completed and updated the `orders_o` object with the necessary logic and database integration. Added a `completed_at` property to track when an order is marked as completed. Includes validation, error handling, and logging to ensure proper functionality.

services/nginx/app/routes/ordersRoute.php

@@ -222,6 +222,44 @@ class ordersRoute
                 'delete_order' => 'Delete an order'
             ]
         );
+
+        $this->post('/orders/mark_as_completed', function () {
+            // Require the user to be logged in
+            global $response;
+            $this->requirePermission('mark_order_as_completed');
+            // Get the user object
+            $user = (new authentication())->get_user();
+            // Check if the request was successful
+            if ($user) {
+                // Get the post data
+                $data = json_decode(file_get_contents('php://input'), true);
+                // Check if the required fields are set
+                if (!isset($data['id'])) {
+                    $response->error('ID is required', 400);
+                }
+                // Get the current order
+                $order = (new orders_o())->getOrderById((int)$data['id']);
+                // Check if the order exists
+                if (!$order->exists()) {
+                    $response->error('Order not found', 400);
+                }
+                // Mark the order as completed
+                $order->markAsCompleted();
+                // Log the incident
+                (new logs_o())->add('orders', $order->department_id->value(), 1, $user->id, 'MARK_ORDER_AS_COMPLETED', 'Successfully marked an order as completed (ID: ' . $data['id'] . ')');
+                // Return a success message
+                $response->success(['message' => 'Order marked as completed successfully']);
+            } else {
+                // Log the incident
+                (new logs_o())->add('orders', 'global', 1, 0, 'MARK_ORDER_AS_COMPLETED', 'No user found, or invalid session');
+                // Return an error
+                $response->error('Invalid session', 400);
+            }
+        },
+            [
+                'mark_order_as_completed' => 'Mark an order as completed'
+            ]
+        );
     }
 
     /**