Resolve remaining backend full-scan Qodana findings (#315)

Fix the two High findings exposed by the first full master Qodana scan after the broader remediation.

services/nginx/app/routes/moduleXLVaskRoute.php

@@ -187,10 +187,10 @@ class moduleXLVaskRoute
             // Create the xlvask tasks object
             $xlvask = new xlvask();
             // Run the sync usage task
-            $result = $xlvask->getTasks()->runSyncUsage();
+            $xlvask->getTasks()->runSyncUsage();
             // Response
             $response->success(
-                $result,
+                null,
                 200
             );
         },

services/nginx/app/tests/selfserve/StopTurnsOffRelayTest.php

@@ -10,7 +10,7 @@ namespace {
 // Provide minimal stubs to satisfy includes without hitting DB/Redis
 namespace classes { class db { public function escape_string($s){ return (string)$s; } }
     class object_property { public function __construct($t=null,$i=null,$n='',$type='',$nullable=false){} public function value(){ return null; } } }
-namespace traits { trait db_object_t { protected string $table=''; protected int $id=0; public function setTable(string $t){ $this->table=$t; } public static function add_object(array $fields){ return 1; } public function select($id){ $this->id=(int)$id; return $this; } public function requireSelected(): void {} public function delete(): void {} } }
+namespace traits { trait db_object_t { protected string $table=''; protected int $id=0; public function setTable(string $t){ $this->table=$t; } public static function add_object(array $data){ return 1; } public function select($id){ $this->id=(int)$id; return $this; } public function requireSelected(): void {} public function delete(): void {} } }
 namespace objects { class department_lanes_o { public $department; public $relay_machine_id; public $relay_machine_program_picker_id; public $relay_machine_cleaner_id; public function __construct(int $departmentId = 0, string $relayId = ''){ $this->department = new \_ValueHolder($departmentId); $this->relay_machine_id = new \_ValueHolder($relayId); $this->relay_machine_program_picker_id = new \_ValueHolder(''); $this->relay_machine_cleaner_id = new \_ValueHolder(''); } public function exists(): bool { return true; } } }
 
 namespace modules\selfserve\classes {